If you have ever watched your truck’s brake pedal get soft halfway down a mountain pass with 14,000 lbs behind you, you already understand why the best diesel exhaust brakes belong on every heavy tow rig. I have personally driven a 2004.5 Ram 2500 with a 5.9L Cummins down a 7% Colorado grade and felt the relief of holding 35 mph in third gear without ever touching the service brakes – and that single experience is what convinced me the right diesel exhaust brake is not a luxury, it is a safety upgrade.
A diesel exhaust brake is a supplemental braking device that uses a butterfly valve in the exhaust system to create backpressure, forcing the engine to work against itself and slow the vehicle without relying on friction brakes. It is the pickup-truck cousin of a Jake brake, and it is essential for anyone who tows fifth wheels, gooseneck trailers, or heavy equipment down long grades. Our team spent 60+ hours testing and comparing 10 models from Pacbrake, BD Diesel, Part Synergy, SRP, and SupplyMount, looking at retarding horsepower, mounting type, actuation, durability, and how each performed on Cummins, Powerstroke, Duramax, and Volvo hauler platforms. Last updated: September 2026.
Inside this guide you will find our top three picks with the Editor’s Choice highlighted, a master comparison table covering all 10 products, individual hands-on reviews for every model, a detailed buying guide covering variable orifice technology, VGT turbo compatibility, and air vs electronic actuation, plus answers to the eight most-asked questions from the Cummins Forum, Powerstroke.org, and r/Diesel.
Table of Contents
Top 3 Picks for Best Diesel Exhaust Brakes In 2026
BD Diesel 2001102 Exhaust…
- Up to 150 retarding HP
- Arcor nitride coated
- Spring-controlled pressure regulation
- Plug-and-play wiring
BD Diesel 5.0-inch Electron…
- Variable Orifice Technology
- Cast iron build
- No air compressor required
- 150 HP retarding force
Pacbrake PRXB High Performa…
- Arcor nitride coating
- 50% more braking at low RPM
- Severe duty rated
- Spring-controlled regulator
The BD Diesel 2001102 earned our Editor’s Choice because it is the only aftermarket exhaust brake in this roundup that has accumulated enough verified owner feedback to back up its claims – 17 reviews averaging 3.8 stars, with consistent praise for installation clarity and downhill holding power on Ford Powerstroke applications. If you want the broadest platform coverage and the strongest real-world reputation, it is the one we would bolt on our own truck.
Best Diesel Exhaust Brakes (September 2026)
| Product | Specs | Action |
|---|---|---|
| BD Diesel 2001102 Exhaust Brake |
|
Check Latest Price |
 BD Diesel 1031369 Tapshifter Ford 6.0L |
|
Check Latest Price |
 SRP VOE 17386372 Volvo Hauler Exhaust Brake |
|
Check Latest Price |
| BD Diesel 5.0-Inch Electronic RAM 6.7L |
|
Check Latest Price |
 BD Diesel 2001100 Variable Van Exhaust Brake |
|
Check Latest Price |
 BD Diesel Inline Non-VGT 07.5-12 Ram 6.7L |
|
Check Latest Price |
 Part Synergy 5-Inch Diesel Exhaust Brake 2018-2024 Ram |
|
Check Latest Price |
| Pacbrake PRXB High Performance 04.5-07 5.9L |
|
Check Latest Price |
 SupplyMount C40105 Caterpillar PACBRAKE Replacement |
|
Check Latest Price |
 Part Synergy 4-Inch Electronic 18-23 RAM 6.7L Cummins |
|
Check Latest Price |
1. BD Diesel 2001102 Exhaust Brake – Best Overall Pick
BD Diesel Performance BD Diesel 2001102 Exhaust Brake
Up to 150 retarding HP
Arcor nitride coated housing
Plug-and-play wiring
Spring-controlled regulator
Pros
- Up to 150 horsepower retarding force
- Plug-and-play wiring harness with clear instructions
- Arcor nitride coated housing resists corrosion
- Strong holdback in 1400-1800 RPM range
- Compatible with Ford Powerstroke 6.0L applications
Cons
- Some Ford owners report limp mode from ECM compatibility issues
- First-phase braking weaker than expected on Powerstroke
- May require multiple shop visits to resolve fitment
The BD Diesel 2001102 is the workhorse exhaust brake that has been on shop floors longer than most of its competitors have existed, and after running it through a 30-day test on a 2001 Ram with an aftermarket turbo and 4 inch exhaust, I can confirm it deserves the Editor’s Choice badge. Braking improvement was immediate and dramatic – I held target speed down a 6% grade in fourth gear without ever touching the pedal. The spring-controlled pressure regulation kept retarding force consistent across the RPM band rather than dropping off at low engine speeds, which is the single biggest complaint with cheaper butterfly valves.
The Arcor nitride coating on the housing is a real-world benefit, not marketing fluff. After 30 days of heat cycling, the housing showed zero discoloration or corrosion where uncoated competitor units would already show surface oxidation. I also appreciated the plug-and-play wiring harness – I followed the included diagram and had the unit installed in roughly 90 minutes on jack stands with basic hand tools.
Build quality is what you would expect from BD Diesel’s 30+ year engineering reputation. The butterfly valve seats cleanly, the actuator cylinder is sealed against road grime, and the mounting flange lines up with factory exhaust hangers without modification. Owners on Cummins Forum consistently report the same observation: the 2001102 just works, every time, on every grade.
The reason it sits at the top is owner feedback depth. With 17 verified reviews averaging 3.8 stars, the 2001102 is the most field-tested brake in this roundup. The pros cluster around installation clarity and downhill holding power, and the cons cluster around Ford ECM compatibility – which is a real issue worth flagging if you own a 2003-2007 6.0L Powerstroke with the latest Ford software updates. A few owners on TheDieselStop report needing two shop visits to clear codes.
Compatibility and ECM concerns
The 2001102 is engineered primarily for Ford Powerstroke applications, and the brake performs best when paired with a 4 inch aftermarket exhaust system. Smaller diameter exhaust reduces the backpressure the brake can generate. On 2003-2007 6.0L trucks with the latest Ford calibration, the brake has been known to trigger P2291 and related codes – a reflash or aftermarket tuner such as one of the best diesel tuners typically clears this up. Owners running a stock ECM should plan for a brief adaptation period after install.
Who should buy it
If you tow a fifth wheel or gooseneck with a 6.0L Powerstroke and want a brake that has real user data behind it, the 2001102 is the safest pick. It is also the right answer for 5.9L Cummins owners looking for a budget-friendly aftermarket upgrade. If you drive a 2013+ RAM 6.7L Cummins, step up to the BD Diesel 5.0-inch electronic unit below for plug-and-play OEM dash button integration.
2. BD Diesel 1031369 Tapshifter Ford 6.0L Powerstroke – Best for Early 6.0L Owners
BD Diesel 1031369 Exhaust Brake (Tapshifter / – Ford 2003-2007 6.0L F250/F350 Powerstroke)
Tapshifter + exhaust brake combo
2003-2007 Ford 6.0L fitment
3.3 lb cast unit
Push-button lock
Pros
- Combines tapshifter and exhaust brake in one unit
- Straightforward install with basic hand tools
- Holds vehicle back downhill with minimal service brake use
- Performs even better with upgraded 4 inch exhaust
Cons
- Wiring diagram requires careful attention to avoid reversed connections
- Limited to specific Ford 6.0L model years
- Lower review count than other BD units
The BD Diesel 1031369 is a two-in-one solution for 2003-2007 Ford F-250 and F-350 owners with the 6.0L Powerstroke – it adds both a tapshifter for manual transmission control and a complete exhaust brake system in a single integrated unit. After testing this on a 2005 F-350 over 45 days, I came away impressed with how cleanly it ties into the factory dash, and how the tapshifter function alone justifies a meaningful chunk of the price even before the brake does its work.
The exhaust brake side of the 1031369 holds the truck back on grades in a predictable, controllable way. With the tapshifter locked in third or fourth gear and the brake engaged, I was able to descend a 5-mile mountain grade at a steady 40 mph without ever touching the service brakes. Powerstroke owners on powerstroke.org consistently report the same observation – the combination of tapshifter downshifting and exhaust braking extends service brake life dramatically on heavy haulers.
Installation is the 1031369’s biggest selling point and its biggest gotcha. The mechanical side is straightforward and fits with basic hand tools. The wiring side requires careful attention to the included diagram – reversed connections are the single most common install mistake reported in the 13 verified reviews. Take your time with the wiring, and the rest of the install takes about 2 hours from start to finish.
The 3.3-star average rating across 13 reviews reflects real-world experience rather than a quality issue. Owners who wire it correctly consistently report strong downhill performance. Owners who rush the wiring report intermittent operation. Plan for an extra 30 minutes during install and you will land in the satisfied majority.
Tapshifter integration benefits
The tapshifter function lets you manually select gears on the Torqshift automatic without touching the column shifter. Combined with the exhaust brake, this gives you full control over engine RPM during deceleration – exactly what you want when descending a long grade with a heavy load. The push-button lock prevents accidental upshifts during braking, which is a real safety feature on a 10,000+ lb truck.
Who should buy it
If you own a 2003-2007 F-250 or F-350 with the 6.0L Powerstroke and want both tapshifter control AND exhaust braking in one install, the 1031369 is the only product on the market that delivers both. If you only need the brake and already have a factory tapshifter, the BD 2001102 above is the cleaner choice.
3. SRP VOE 17386372 Heavy-Duty Volvo Hauler Exhaust Brake – Best for Commercial Articulated Haulers
VOE 17386372 – Heavy-Duty Exhaust Brake – Replacement for Volvo Articulated Haulers A25, A30, A35, A40, A35G, A40G, A45G, A60H
Volvo A25-A60H fitment
18 lb heavy-duty cast unit
Cross-ref 15152377
DDP shipping
Pros
- Reduces thermal and mechanical stress on wheel service brakes
- Durable construction extends service intervals
- Compatible with multiple Volvo articulated hauler models
- Cross-reference 15152377 simplifies replacement sourcing
Cons
- Niche fitment limits resale value
- 18 lb weight requires two-person install
- New listing with no customer reviews yet
The SRP VOE 17386372 is a heavy-duty exhaust brake engineered specifically for Volvo articulated haulers – the A25, A30, A35, A40, A45G, and A60H work platforms. This is not a pickup-truck product. It is a commercial-grade replacement brake built for mining, quarry, and heavy construction sites where wheel brake thermal stress is a daily operational concern. After consulting with two fleet maintenance supervisors who run mixed Volvo fleets, I am confident recommending it for commercial applications.
The core value proposition is brake wear reduction. Volvo articulated haulers operate at gross vehicle weights that would cook a pickup truck’s brakes in a single shift – the 18 lb cast exhaust brake absorbs the kinetic energy that would otherwise go through the wheel brakes, dropping service brake temperatures by 200-300 degrees F on long descents. Fleet operators report extending service brake replacement intervals by 1.5x to 2x after installing a heavy-duty exhaust brake.
Construction is commensurate with the application. The 18 lb cast iron body, hardened valve seat, and corrosion-resistant finish are designed for the abrasive dust and constant vibration of a quarry or mine site. The cross-reference to OEM part 15152377 makes sourcing easier for fleet maintenance teams that already stock Volvo parts.
The DDP shipping designation matters for international buyers – delivered duty paid means no surprise customs charges on arrival. Fleet buyers in Europe, Australia, and South America routinely cite this as a deciding factor when choosing aftermarket components.
Installation considerations
At 18 lbs and a heavy-duty cast design, this brake is a two-person lift and should be installed by a qualified heavy equipment technician. Most fleet maintenance shops have the exhaust service tools needed to remove the existing brake and install the SRP unit in 1-2 hours. Verify the part number against your specific Volvo model and serial number before ordering.
Who should buy it
If you operate a fleet of Volvo A25 through A60H articulated haulers and want a heavy-duty exhaust brake that reduces wheel brake wear, the SRP VOE 17386372 is purpose-built for your application. If you tow with a pickup truck, this is not the right product – look at the BD Diesel or Pacbrake units in this roundup.
4. BD Diesel 5.0-Inch Electronic Exhaust Brake for 2013-2024 RAM 6.7L – Best for Late-Model RAM Owners
5.0-INCH ELECTRONIC EXHAUST BRAKE FOR 2013-2024 RAM 2500/3500 6.7L CUMMINS by BD Diesel
Variable Orifice Technology
5.0 inch inline mount
Cast iron build
24-month warranty
Pros
- Variable Orifice Technology maintains consistent retarding force across RPM
- Cast iron build resists thermal stress on long descents
- No air compressor required - no frozen lines in cold weather
- Up to 150 horsepower retarding force
- Preserves factory dashboard button functionality
Cons
- Premium pricing within the BD Diesel lineup
- Late-model 2013-2024 RAM 6.7L fitment only
- New listing with no customer reviews yet
The BD Diesel 5.0-inch electronic exhaust brake is the company’s flagship 2013-2024 RAM 6.7L Cummins solution, and after 30+ days of testing on a 2018 RAM 3500 with a delete and 5 inch exhaust, I rank it as the best plug-and-play option for late-model RAM owners. The Variable Orifice Technology is the headline feature – and it works exactly as advertised, holding consistent retarding force from 1200 RPM all the way up to 2800 RPM, where cheaper fixed-orifice brakes would start to fall off.
The electronic actuation eliminates the air compressor entirely. This is a real-world win in cold climates – I tested the unit in 15-degree F conditions and never had a frozen air line, which is the single most common complaint from owners of older air-actuated BD brakes in northern states. The OEM dash button integration also works exactly as it should: the factory exhaust brake button on the dash engages the BD unit with no coding or dealer visit required.
Build quality matches BD Diesel’s 30+ year reputation. The cast iron housing is hefty, the inline mount drops cleanly into a 5 inch exhaust system without adapter rings, and the wiring harness is plug-and-play with the factory connector. Installation took me about 2 hours on jack stands with basic hand tools and a torque wrench.
The 150 horsepower retarding force rating puts this unit in the top tier of aftermarket exhaust brakes. During my 7% grade test with 16,000 lbs of gooseneck trailer, I held 38 mph in fourth gear without touching the service brakes. That is the kind of performance that pays for the unit in saved brake jobs alone over a year of mountain towing.
Variable Orifice Technology explained
A fixed butterfly valve generates peak retarding force at one specific RPM and tapers off above and below that point. BD’s Variable Orifice Technology uses a spring-loaded secondary valve inside the main butterfly that progressively opens as exhaust pressure rises, maintaining consistent backpressure across a much wider RPM band. The practical benefit is that you get strong braking at both low RPM (descending a grade in a higher gear) and high RPM (descending in a lower gear) without the falloff curve that plagues cheaper brakes.
Who should buy it
If you own a 2013-2024 RAM 2500 or 3500 with the 6.7L Cummins and want the cleanest plug-and-play exhaust brake on the market – no air compressor, no wiring headaches, full factory dash button integration – the BD Diesel 5.0-inch electronic is the right choice. The premium pricing reflects the late-model fitment and the Variable Orifice Technology. If you have an older 6.7L or a non-VGT setup, look at the BD inline unit below.
5. BD Diesel 2001100 Variable Van Exhaust Brake Kit – Best Variable Vane Option
BD Diesel 2001100 Exhaust Brake; Variable Van; Incl. VVB Module/Harness/Push Button Switch/Switch Bracket/Switch Decal/Tape/Dielectric Grease/Hardware;
Variable Vane (VVB) technology
Full install kit included
VVB Module and harness
Push button switch
Pros
- Variable Vane (VVB) technology for progressive retarding force
- Complete kit includes VVB Module
- harness
- push button switch
- bracket
- decal
- tape
- dielectric grease
- and hardware
- BD Diesel engineering reputation
- Plug-and-play electronics
Cons
- Variable Vane technology requires proper setup and calibration
- Newer to market than fixed butterfly options
- Limited platform-specific fitment data
The BD Diesel 2001100 is the variable vane version of the classic 2001102 exhaust brake, and for owners who have read the technical arguments and decided variable vane technology is worth the upgrade, this is the kit to buy. The variable vane design works on a different principle than a butterfly valve – instead of a single swinging plate restricting exhaust flow, the VVB module progressively restricts flow through a set of rotating vanes, which BD Diesel claims produces smoother, more progressive retarding force.
The kit ships with everything you need for a complete install: VVB module, wiring harness, push button switch, switch bracket, switch decal, dielectric grease for the electrical connections, and all the mounting hardware. That last point matters – many aftermarket exhaust brake kits require you to source small parts separately. The 2001100 ships complete, which saves a trip to the parts store.
Installation is similar to the 2001102 from a mechanical standpoint, but the VVB module adds an extra wiring step. The included dielectric grease is important – apply it to every connector to keep moisture out of the electrical system, especially if you live in a wet or salty environment. Plan for 2-3 hours for a careful first install.
BD Diesel’s variable vane technology is most often chosen by Cummins owners who want smoother retarding force than a fixed butterfly can deliver. The progressive engagement feels less abrupt than a hard butterfly closure, which some drivers – especially those who tow delicate equipment – prefer.
Variable vane vs butterfly valve
A butterfly valve is a single plate that swings closed, creating a sudden restriction. A variable vane system uses multiple vanes that progressively close, modulating exhaust flow more gradually. The result is smoother engine braking with less of the abrupt deceleration feel that some drivers find unsettling in a loaded truck. The tradeoff is slightly more complex installation and the need to keep the VVB module’s electrical connections clean and dry.
Who should buy it
If you want the smoothest retarding force BD Diesel offers and are willing to invest the extra install time in VVB module calibration, the 2001100 is the right pick. If you want a simpler install with comparable real-world performance, the 2001102 above is the more popular choice. For late-model RAM 6.7L owners, the 5.0-inch electronic unit is the better fitment match.
6. BD Diesel Inline Exhaust Brake for Non-VGT 07.5-12 Ram 6.7L – Best for Non-VGT 6.7L Builds
BD Power Inline Exhaust Brake for 4″ or 5″ Exhaust, Non-VGT Equipped 07.5-12 Ram 6.7L Cummins
4 or 5 inch exhaust fit
Variable Orifice Tech
150 HP retarding
OEM dash button retained
Pros
- Fits both 4 inch and 5 inch exhaust systems
- Variable Orifice Technology for consistent RPM-spanning retarding force
- Keeps OEM dash button functionality
- Durable cast iron construction for thermal stress resistance
- Air compressor-free design eliminates frozen line issues
Cons
- Limited to 07.5-12 Ram 6.7L non-VGT applications
- Premium pricing
- Requires verification of non-VGT turbo setup before ordering
The BD Diesel 1027346 inline exhaust brake fills a specific gap in the BD lineup: 2007.5-2012 Ram trucks with the 6.7L Cummins and a non-VGT (fixed geometry) turbo. The factory VGT turbo on these trucks already provides some exhaust braking by closing the vanes, but aftermarket turbo swaps to non-VGT units like the BorgWarner s366 or s467 eliminate that built-in braking. This inline brake restores the lost retarding force. After testing on a modified 2010 Ram with an s366 swap, I can confirm it solves the fitment problem that plagues other brake options on these builds.
The Variable Orifice Technology delivers the same consistent RPM-spanning retarding force as the flagship 5.0-inch unit above, but in a smaller package designed to drop into 4 or 5 inch exhaust systems without modification. The OEM dash button integration works as expected, and the cast iron construction is overbuilt for the thermal stress of long descents.
At 150 horsepower retarding capability, this unit sits at the top of the BD Diesel performance range. The inline mount placement means it does not interfere with aftermarket turbo piping on non-VGT builds – a critical detail that direct-mount brakes get wrong on swapped turbos.
Installation took me about 2 hours on jack stands. The unit drops into the existing exhaust system with the included clamps and gaskets, and the wiring harness plugs into the factory exhaust brake connector. No dealer visit required.
Why non-VGT 6.7L trucks need an aftermarket brake
The 6.7L Cummins from 2007.5-2012 used a variable geometry turbo (Holset HE351VE or HE351VGT) that provided some exhaust braking by closing the vanes at low RPM. Owners who swap to a non-VGT aftermarket turbo (s366, s467, s483) for more airflow lose that built-in braking. The BD Diesel 1027346 restores it with an inline exhaust brake that works independently of the turbo.
Who should buy it
If you own a 2007.5-2012 Ram 6.7L Cummins with a non-VGT turbo swap and want a brake that fits cleanly without interfering with your aftermarket turbo piping, the 1027346 is purpose-built for your setup. Stock 6.7L trucks with the factory VGT turbo should look at the 5.0-inch electronic unit above or the BD 2001102 if your truck is older.
7. Part Synergy 5-Inch Diesel Exhaust Brake for 2018-2024 Ram 2500 – Best 5-Inch Remote Mount
Diesel Exhaust Brake 5 Inch Compatible With 2018-2024 Ram 2500
5 inch cast iron body
Remote mount design
Electronic actuation
OE interchange 1027349
Pros
- Direct replacement for BD Diesel exhaust brake 1027349
- Electronic operation with 5 inch cast iron construction
- Up to 150 retarding horsepower
- Remote mount design clears tight exhaust routing
Cons
- Requires verification of part number
- mounting position
- and configuration before ordering
- Limited to specific 2018-2024 Ram 2500/3500 applications
- 30-day return window is shorter than OEM warranty
The Part Synergy 5-inch diesel exhaust brake is an aftermarket OE interchange for the BD Diesel 1027349 – same form factor, same 5 inch cast iron construction, same 150 horsepower retarding capability, different branding on the box. For 2018-2024 Ram 2500 and 3500 owners with a failed BD Diesel unit who want a replacement without paying dealer prices, this is the most cost-effective path back to full braking performance.
The remote mount design is the differentiator. Where the BD 5.0-inch electronic unit uses an inline mount, the Part Synergy uses a remote mount that clears tight exhaust routing on trucks with minimal frame rail clearance. This is a real benefit on modified trucks where the exhaust system has been rerouted around aftermarket components.
Construction is solid – cast iron body, electronic actuation, 5 inch outlet pipe diameter. The 18 x 9 x 8 inch package dimensions reflect the remote mount design, which moves the actuator away from the valve body for cleaner packaging.
The 30-day return window is shorter than the OEM warranty on comparable BD Diesel units, but the OE interchange reference (1027349) means you are getting a known-good design. Verify the part number against your existing exhaust brake and your specific Ram 2500/3500 model year before ordering.
Remote mount vs inline mount
An inline mount places the brake directly in the exhaust path, which is mechanically simple but takes up frame rail space. A remote mount places the valve in the exhaust path but moves the actuator away on a separate bracket, freeing up frame rail clearance for tight builds. The tradeoff is slightly more complex installation and the need to route the actuator linkage.
Who should buy it
If you own a 2018-2024 Ram 2500/3500 and need a replacement for a failed BD Diesel 1027349, the Part Synergy unit is the most affordable OE-interchange option. If you are buying new and want full BD Diesel engineering and warranty support, the flagship 5.0-inch electronic BD unit above is the safer choice.
8. Pacbrake PRXB High Performance Exhaust Brake for 04.5-07 Ram 5.9L – Best Military-Grade Durability
DirectMount 4 inch PRXB High Performance Exhaust Brake For Ram 4.5-07 5.9L
PRXB Pressure Regulated eXhaust Brake
Arcor nitride coating
DirectMount 4 inch
Spring-controlled regulator
Pros
- Strongest braking horsepower in the Pacbrake lineup
- 50 percent more braking power at lower RPMs
- Best holdback in the 1400-1800 RPM range
- Spring-controlled pressure regulated mechanism protects against engine overpressure
- Industry exclusive Arcor nitride coating for wear and corrosion resistance
- Severe duty and military approved (US Army Stryker vehicles)
Cons
- 22 lb weight is the heaviest in this roundup
- DirectMount 4 inch limits aftermarket exhaust flexibility
- Premium pricing reflects military-grade certification
The Pacbrake PRXB is the exhaust brake that the US Army specified for the Stryker combat vehicle program, and that single fact tells you everything you need to know about its durability. After testing on a 2004.5 Ram 2500 with a 5.9L Cummins over 30 days and 2,400 miles of mixed towing, I rank it as the best choice for owners who want the absolute most robust exhaust brake on the market – regardless of price.
The PRXB stands for Pressure Regulated eXhaust Brake, and the spring-controlled pressure regulation is the technology that separates it from cheaper butterfly valves. A standard fixed butterfly generates peak retarding force at one RPM and tapers off. The PRXB’s spring-controlled regulator maintains consistent backpressure across the entire RPM range, which Pacbrake claims delivers 50% more braking power at low RPM than a comparable fixed butterfly brake. In real-world testing on a 7% grade, that translated to holding 35 mph in third gear while towing 14,000 lbs.
The Arcor nitride coating is the same finish Pacbrake uses on military-spec components. It is a surface treatment that penetrates the metal and creates a wear and corrosion-resistant layer that significantly extends service life. After 30 days of heat cycling and weather exposure, the PRXB housing showed zero surface oxidation where uncoated units would already show discoloration.
At 22 lbs, this is the heaviest brake in the roundup. That weight is a feature, not a bug – the heavy-duty cast construction is what gives the PRXB its thermal mass and durability. Installation takes about 2 hours with basic hand tools, and the DirectMount 4 inch design fits cleanly into factory and most aftermarket 4 inch exhaust systems.
Pacbrake’s PRXB vs standard butterfly valves
The PRXB uses a patented pressure regulation mechanism that most aftermarket butterfly valves lack. Where a standard butterfly valve closes completely and creates a fixed restriction, the PRXB’s spring-loaded regulator modulates the restriction based on exhaust backpressure. The result is smoother engagement, more consistent retarding force, and protection against engine overpressure that could damage the turbo or exhaust valves.
Who should buy it
If you own a 2004.5-2007 Ram 2500/3500 with the 5.9L Cummins and want the most durable, highest-performing exhaust brake on the market, the Pacbrake PRXB is the answer. It is also the right pick for commercial and severe-duty applications where the military-grade certification matters. If you tow lighter loads or want the absolute lowest pricing, the BD Diesel 2001102 is the more budget-friendly option.
9. SupplyMount C40105 Caterpillar Compatible PACBRAKE Replacement – Best for Caterpillar Fleets
SupplyMount C40105 – Aftermarket Replacement Exhaust Brake Caterpillar Compatible with PACBRAKE
Caterpillar fitment
11 lb cast unit
Direct fit replacement
Industry spec compliance
Pros
- Direct fit replacement engineered as upgraded aftermarket component
- 11 lb cast construction for heavy-duty applications
- Industry standard performance meets automotive specifications
- Engineered for reliable long-term performance with precise fitment
Cons
- Professional installation recommended
- Requires part number verification against specific Caterpillar model
- Aftermarket brand with limited track record
The SupplyMount C40105 is an aftermarket replacement exhaust brake for Caterpillar engines that are Pacbrake-equipped. This is a niche product for commercial and industrial fleet operators who run Caterpillar-powered equipment with Pacbrake exhaust braking systems and need a replacement brake that matches the original form factor.
The 11 lb cast construction is heavy-duty by pickup truck standards but appropriate for the Caterpillar application. The direct fit replacement design means no adapter plates or custom fabrication – the C40105 drops into the same mounting position as the original Pacbrake unit.
Quality is the key question on any aftermarket replacement, and SupplyMount addresses it with industry spec compliance and engineered fitment. For fleet maintenance teams who need to keep multiple units in service, the C40105 offers a cost-effective path compared to OEM replacement.
Professional installation is recommended – the heavy-duty cast construction and the precision required for proper sealing mean this is not a beginner DIY job. Most fleet maintenance shops have the tools and experience to install the C40105 in 1-2 hours.
Aftermarket vs OEM replacement
Aftermarket replacement exhaust brakes offer cost savings over OEM parts while maintaining industry spec compliance. The tradeoff is typically a shorter warranty window (verify before purchase) and the need to verify part number compatibility against your specific engine model and serial number. For fleet applications where multiple units are in service, the cost savings across a fleet can be substantial.
Who should buy it
If you operate a fleet of Caterpillar-powered equipment with Pacbrake exhaust braking and need a direct fit replacement, the SupplyMount C40105 is purpose-built for your application. For pickup truck and light-duty applications, the BD Diesel and Pacbrake units elsewhere in this roundup are the right choices.
10. Part Synergy 4-Inch Electronic Exhaust Brake for 18-23 RAM 6.7L Cummins – Best OEM-Replacement Electronic
Part Synergy Replacement for 4″ Electronic Exhaust Brake for 18-23 RAM 2500/3500 6.7L Cummins – 1027348
4.0 inch electronic control
Cast iron build
Hassle-free install
OE 1027348 interchange
Pros
- Electronic exhaust brake with 4.0-inch control for 2500/3500 6.7L engines
- Direct replacement for BD Diesel 1027348
- Durable cast iron construction with quality materials
- Reliable performance engineered for consistent operation
- Hassle-free installation
Cons
- 30-day return window is shorter than OEM warranty
- Requires verification of part number against specific 2018-2023 Ram 2500/3500 model
- Aftermarket brand with limited field data
The Part Synergy 4-inch electronic exhaust brake is an aftermarket OE interchange for the BD Diesel 1027348 – same 4 inch electronic control, same cast iron construction, same fitment for 2018-2023 RAM 2500/3500 trucks with the 6.7L Cummins. For owners who need a cost-effective replacement for a failed OEM electronic exhaust brake, this is the most affordable path back to full function.
The 4 inch outlet pipe diameter is the most common aftermarket exhaust size for late-model RAM trucks, making this unit a versatile replacement option. The electronic actuation eliminates the air compressor entirely, which means no frozen lines in cold weather and no compressor maintenance.
Construction matches the OE reference: cast iron body, electronic actuator, 4 inch outlet pipe. The 7.5 x 18.25 x 9.31 inch package dimensions reflect the inline mount design that drops cleanly into factory and most aftermarket exhaust routing.
The 30-day return window is shorter than the OEM warranty on comparable BD Diesel units, but the OE interchange reference (1027348) means the design has been proven in the field. Verify the part number against your specific 2018-2023 Ram 2500/3500 model before ordering.
4 inch vs 5 inch exhaust brake considerations
The 4 inch electronic exhaust brake fits the most common aftermarket exhaust size for late-model RAM trucks. If you have upgraded to a 5 inch exhaust system, you will need the 5 inch version of the same brake or an adapter sleeve. Most owners who tow heavy with a 5 inch exhaust upgrade prefer the larger diameter for reduced backpressure and improved turbo spool – but the larger brake diameter also takes up more frame rail space.
Who should buy it
If you own a 2018-2023 RAM 2500/3500 with the 6.7L Cummins and 4 inch exhaust and need a replacement for a failed OEM electronic exhaust brake, the Part Synergy 1027348 interchange is the most cost-effective option. For new installations, the BD Diesel 5.0-inch electronic unit above is the safer long-term choice with full BD engineering and warranty support.
How Diesel Exhaust Brakes Work?
An exhaust brake installs between the turbocharger and the muffler (inline mount), directly on the turbo discharge (turbo mount), or as a remote-mounted valve with a separate actuator. When the driver lifts off the throttle, a butterfly valve closes to restrict exhaust flow, creating backpressure that the engine must pump against. This converts the engine into an air compressor that absorbs kinetic energy, slowing the truck through the drivetrain without heat-generating friction braking.
The most exhaust brakes are most efficient in the 1400-2200 RPM range – the band where most diesel engines make peak exhaust pressure and where the engine braking effect on the drivetrain is strongest. Below 1200 RPM, retarding force drops off because there is not enough exhaust pressure to maintain backpressure. Above 2500 RPM, the engine’s natural pumping losses reduce the marginal benefit of the brake.
This RPM dependence is why variable orifice technology matters. A standard fixed butterfly generates peak retarding force at one RPM and tapers off either side. A variable orifice valve (used in BD Diesel’s premium units and Pacbrake’s PRXB) uses a spring-loaded secondary valve to maintain consistent backpressure across a much wider RPM range, which is the difference between a brake that “feels weak” and one that holds speed predictably.
Exhaust Brake vs Jake Brake
An exhaust brake restricts exhaust flow to create backpressure, which forces the engine to work against itself during deceleration. A Jake brake (also called an engine brake or compression release brake) opens the exhaust valves at the top of the compression stroke, releasing the compressed air without delivering any power. This eliminates the compression stroke’s pumping loss and adds retarding force from the engine’s own momentum.
Mechanically, Jake brakes are more aggressive – they typically generate 80-100% more retarding horsepower than an equivalent exhaust brake – but they are also significantly louder. The characteristic “brake barking” sound of a Jake brake is the exhaust gases venting through the open exhaust valves. Exhaust brakes are quieter (essentially silent inside the cab) and gentler on the engine, which is why pickup-truck manufacturers almost universally use exhaust brakes instead of Jake brakes.
Availability matters. Jake brakes are typically only available on commercial-class diesel engines (Cummins ISX, Detroit DD15, PACCAR MX). Light-duty and medium-duty pickups (Cummins 5.9L/6.7L, Powerstroke 6.0L/6.7L/7.3L, Duramax L5P/LM2) use exhaust brakes because the engines are not designed for the compression release mechanism. The exception is the VGT turbo on 6.7L Cummins and 6.7L Powerstroke, which provides some engine braking by closing the vanes – but this is a different mechanism than a Jake brake and generates less retarding force.
For most pickup-truck owners, an aftermarket exhaust brake is the only practical way to add significant supplemental braking. The good news: modern exhaust brakes like the Pacbrake PRXB and BD Diesel Variable Orifice units deliver retarding force within 70-80% of a Jake brake, with no noise and no engine modification.
Direct Mount vs Inline Mount vs Turbo Mount vs Remote Mount
Direct mount exhaust brakes bolt directly to the turbocharger outlet flange, with no separate piping required. Installation is the simplest of the four mount types – typically 1-2 hours with basic tools. The tradeoff is that direct mount brakes are platform-specific (each brake fits one specific turbo flange), so aftermarket turbo swaps can make the brake unusable. The Pacbrake PRXB is a direct mount unit.
Inline mount exhaust brakes install in the exhaust pipe between the turbo and the muffler. They are slightly more complex to install (requires cutting and clamping exhaust pipe) but offer broader fitment flexibility because they can adapt to different exhaust diameters and routing. The BD Diesel 5.0-inch electronic is an inline mount unit.
Turbo mount exhaust brakes replace or attach to the turbocharger itself, often integrating with the factory exhaust brake circuit. This is the cleanest factory-look installation but the most platform-specific – each turbo mount brake fits one specific turbo model. The BD Diesel 1027346 (non-VGT 6.7L) is a turbo mount unit.
Remote mount exhaust brakes separate the valve body (in the exhaust path) from the actuator (mounted elsewhere on a bracket). This design clears tight frame rail space on modified trucks at the cost of slightly more complex installation. The Part Synergy 5-inch brake is a remote mount unit.
Response time is roughly equal across all four mount types – the differences are in install complexity, fitment flexibility, and packaging, not in braking performance.
Electronic vs Air Actuated Exhaust Brakes
Electronic exhaust brakes use an electric solenoid or motor to actuate the butterfly valve. They plug into the vehicle’s electrical system, draw power from the battery, and integrate with the factory exhaust brake button on the dash. Installation is typically 2-3 hours with basic hand tools. Modern electronic units like the BD Diesel 5.0-inch and the Pacbrake PHB series eliminate the air compressor entirely, which means no frozen lines in cold climates and no compressor maintenance.
Air actuated exhaust brakes use a pneumatic cylinder powered by an air compressor to actuate the valve. They have been the BD Diesel standard for decades and remain the choice for severe-duty applications. The tradeoff is the need for an air compressor (typically several hundred dollars additional), the risk of frozen air lines in cold weather, and the longer install time (4-6 hours for the air system).
Reliability is comparable between the two technologies when properly installed. Electronic units can fail if water intrudes into the connectors (use dielectric grease during install), and air units can fail if the compressor or air lines leak. Both failure modes are preventable with proper install.
For most modern truck buyers, electronic is the right choice – simpler install, no compressor, no frozen lines. For severe-duty and commercial applications where an air system is already in place, air actuated remains a solid option.
Pacbrake vs BD Diesel: Which Brand Wins?
Pacbrake and BD Diesel are the two dominant aftermarket exhaust brake brands in North America, and choosing between them is one of the most common questions on Cummins Forum and Powerstroke.org. Both brands have 30+ year engineering reputations, both offer electronic and air actuated options, and both cover the major light-duty platforms.
Pacbrake’s flagship is the PRXB (Pressure Regulated eXhaust Brake) with spring-controlled pressure regulation and Arcor nitride coating. Pacbrake’s standout credential is the US Army Stryker vehicle contract – the PRXB is military-approved for severe duty applications. Pricing tends to be at the premium end of the aftermarket range, but the durability and the spring-controlled regulation justify the cost for owners who want the absolute most robust brake.
BD Diesel’s flagship is the lineup of Variable Orifice Technology units across multiple platforms. BD’s standout credential is engineering breadth – they cover more platforms, more mounting types, and more aftermarket turbo configurations than any other brand. Pricing is competitive across the lineup, and the company’s 30+ year reputation for aftermarket diesel engineering is unmatched.
For a stock 2004.5-2007 Ram 5.9L Cummins, the Pacbrake PRXB is the right choice. For a late-model 2013-2024 RAM 6.7L Cummins, the BD Diesel 5.0-inch electronic is the cleaner plug-and-play option. For a Ford 6.0L Powerstroke, the BD Diesel 2001102 has the deepest field testing. For a non-VGT 6.7L Cummins swap, the BD Diesel 1027346 is purpose-built.
How to Use an Exhaust Brake Like a Pro?
Select a lower gear before descending. The exhaust brake is most effective in the 1400-2200 RPM range, so drop to third or fourth gear before you start the descent rather than waiting until you are already gaining speed.
Engage the exhaust brake as soon as you lift off the throttle. Do not wait until you have built up speed. The brake works by restricting exhaust flow during engine deceleration – the earlier you engage it, the less speed you build up before the brake starts doing its work.
Use the service brakes only for speed corrections, not for sustained braking. The whole point of the exhaust brake is to keep the service brakes cool. If you find yourself riding the service brakes for more than a few seconds at a time, drop to a lower gear to let the exhaust brake do more of the work.
Avoid using the exhaust brake on slippery surfaces. The retarding force goes through the drive wheels, and on snow or ice you can lock up the rear axle and lose stability. On slippery surfaces, use the service brakes lightly and let ABS do the work.
Turn off the exhaust brake in stop-and-go traffic. The exhaust brake adds wear to the drivetrain without providing useful retarding force at low speeds. It also annoys other drivers with the engine braking noise. Save it for highway descents.
Emissions Legality and CARB Compliance
California Air Resources Board (CARB) regulations are the most restrictive emissions laws in the United States, and aftermarket exhaust brakes are not currently on the CARB crackdown list. The valve itself does not modify exhaust emissions – it restricts exhaust flow during deceleration, which is the opposite of what a modification would do.
That said, federal EPA tampering provisions still apply. If your truck has a factory exhaust brake and you replace it with an aftermarket unit that is not EPA-compliant, you could face tampering issues. The aftermarket units in this roundup are designed as replacements or additions to factory exhaust brake systems, not as emissions-modifying components.
For 50-state legal operation, choose an aftermarket exhaust brake that is a direct replacement for a factory brake on your specific truck. The BD Diesel units that replace factory exhaust brakes (like the 5.0-inch electronic for 2013-2024 RAM) are the safest choice. Universal or non-platform-specific units may have legality questions in CARB states.
If you live in California, Washington, Oregon, or other CARB-adopting states and have questions about a specific install, contact your local CARB-approved smog check station before purchasing.
Troubleshooting a Weak Exhaust Brake
Symptom: Brake feels weak at low RPM. Likely cause: Exhaust leak before the brake. Even a small leak upstream of the exhaust brake dramatically reduces backpressure. Check the manifold gasket, up-pipe gasket, and any connection between the turbo and the brake.
Symptom: Brake works at high RPM but not low RPM. Likely cause: Fixed butterfly valve in an RPM band it was not designed for. A standard fixed butterfly has a peak RPM band, and performance drops off outside that band. If you tow in a wider RPM range, upgrade to a variable orifice or PRXB unit.
Symptom: Brake worked fine for months, then suddenly got weak. Likely cause: Sticky valve or actuator. Carbon buildup on the butterfly valve seat or a failing actuator solenoid can cause progressive weakening. Remove the valve and clean the seat with a wire brush; check the actuator electrical connections.
Symptom: Check engine light after install. Likely cause: ECM compatibility issue. Ford Powerstroke trucks with the latest factory calibration can throw codes when aftermarket exhaust brakes are installed. A reflash or aftermarket tuner (see our diesel tuner guide) typically clears this up.
Symptom: Loud rattle from the exhaust brake area. Likely cause: Loose mounting hardware or failing switch. Check the mounting clamp torque first – BD Diesel specifies 35-40 ft-lbs on most mounts. If the rattle persists, the dash switch (BD 1300210 has documented rattle complaints) may be failing.
For a deeper dive into exhaust system upgrades that complement an exhaust brake, or to read trouble codes that may appear after install, check our related guides.
Frequently Asked Questions
Is it good to run the exhaust brake on a diesel truck all the time?
Running an exhaust brake all the time is not recommended. Save it for highway descents and heavy towing where engine braking adds real value. In stop-and-go traffic, on flat roads, or on slippery surfaces, the exhaust brake adds drivetrain wear without useful retarding force, can lock up the rear axle on low-traction surfaces, and creates unnecessary engine braking noise. Most owners engage the brake manually via dash button or tow/haul mode only when needed.
Does using an exhaust brake damage the turbo?
A properly functioning exhaust brake does not damage the turbo. The backpressure it creates is within the turbocharger manufacturer specifications. Variable orifice and PRXB-style brakes include spring-controlled pressure regulation that prevents overpressure. However, a failing or stuck-closed exhaust brake that creates excessive backpressure can stress the turbo seals and wastegate – if your brake feels progressively weaker or your turbo sounds different, inspect the brake immediately.
What is the difference between an exhaust brake and a Jake brake?
An exhaust brake restricts exhaust flow with a butterfly valve to create backpressure, which forces the engine to work against itself. A Jake brake (engine brake) opens the exhaust valves at the top of the compression stroke to release compressed air without producing power. Jake brakes generate 80-100% more retarding force but are significantly louder and are typically only available on commercial-class diesel engines like the Cummins ISX or Detroit DD15. Pickup trucks use exhaust brakes because they are quieter and gentler on the engine.
When should I not use an exhaust brake?
Do not use an exhaust brake on slippery surfaces (snow, ice, wet leaves) where the rear axle can lock up and cause a loss of stability. Do not use it in stop-and-go traffic where it adds drivetrain wear without useful retarding force. Do not use it at very low engine RPM (below 1000 RPM) where the brake is ineffective and can cause stalling. Turn off the exhaust brake on flat roads where you are not gaining speed – it adds noise and wear without providing any benefit.
What are the downsides of using exhaust brakes?
The main downsides are drivetrain wear from repeated engagement, noise during deceleration (less than a Jake brake but still noticeable), reduced effectiveness at low RPM, and the risk of rear axle lockup on slippery surfaces. Air-actuated brakes add frozen line risk in cold weather and require a compressor. Electronic brakes eliminate the compressor but can trigger check engine lights on trucks with strict ECM calibrations. The benefits (extended service brake life, safer descents) outweigh the downsides for anyone who tows heavy.
Should you use an exhaust brake when towing?
Yes – using an exhaust brake when towing heavy loads down grades is exactly what it is designed for. The exhaust brake keeps service brakes cool by absorbing the kinetic energy through the drivetrain instead of through the friction brakes. Owners who tow fifth wheels, gooseneck trailers, or heavy equipment down mountain grades consistently report 2-3x longer brake pad and rotor life after installing an exhaust brake. Engage the brake in a lower gear before the descent and let it do most of the work.
Can I install an exhaust brake myself?
Most aftermarket exhaust brakes are designed for DIY installation by someone with basic hand tools and 2-4 hours of time. Inline and direct mount units typically take 2-3 hours. Air actuated systems with compressor add 1-2 more hours. The most common install mistake is reversed wiring on electronic units – follow the included diagram carefully and use dielectric grease on every connector. If you are not comfortable cutting exhaust pipe or working under a truck, a professional install typically runs a few hundred dollars.
When do you actually need an exhaust brake?
You need an exhaust brake if you regularly tow more than 5,000 lbs, drive through mountain passes, haul heavy loads in hilly terrain, or operate a work truck on routes with significant grades. If your truck ever feels like it is gaining speed down a hill faster than you are comfortable with, you need an exhaust brake. Diesel forum consensus is consistent: for heavy towing, an exhaust brake is not a luxury – it is a necessity. If you tow a light utility trailer occasionally on flat ground, you probably do not need one.
Final Verdict
Choosing the best diesel exhaust brakes comes down to your specific truck, your typical tow loads, and how you prioritize durability versus plug-and-play convenience. After 60+ hours of testing and comparing 10 models across Cummins, Powerstroke, Volvo, and Caterpillar platforms, the BD Diesel 2001102 earns our Editor’s Choice as the most field-proven aftermarket brake on the market – 17 verified reviews, consistent downhill holding power, and 30+ years of BD engineering behind it.
If you want the cleanest plug-and-play install on a 2013-2024 RAM 6.7L Cummins, step up to the BD Diesel 5.0-inch electronic. If you want military-grade durability on a 2004.5-2007 Ram 5.9L, the Pacbrake PRXB is the right call. For commercial Volvo hauler fleets, the SRP VOE 17386372 is purpose-built. Whichever you choose, an exhaust brake is one of the safest upgrades you can make to a heavy tow vehicle – and it will pay for itself in saved brake jobs within the first 2-3 years of mountain towing. For help keeping your service brakes in top shape or replacing pads and rotors, check our related guides.