A transfer tank is a portable fuel reservoir you carry in a pickup bed to refuel equipment that never sees a fuel station, a skid steer on a remote job site, a compact tractor on a ranch, or a generator during an outage. An L-shaped transfer tank is the version cut with a stepped profile so it nests into the corner of the bed and rides up over the wheel wells, giving you more fuel capacity than a slim rectangle tank while keeping usable bed space behind it.
That shape is the whole reason this category exists. Wheel wells and the front corner of a bed are dead space that a rectangle tank has to ignore. Cut the tank into an L and you convert that dead space into gallons, which is why the best L shaped transfer tanks keep showing up as the answer for short-bed owners and for anyone who already owns a crossover toolbox. If you want the wider context on tank formats and fleet fueling, our fleet fuel transfer tank guide covers the basics in more detail.
We compared ten L-shape and L-format units from UWS, Dee Zee, RDS Manufacturing, Weather Guard, and Aluminum Tank Industries. We looked at capacity, empty weight, material, footprint, mounting pattern, and what owners actually say after living with them. Below is the roundup, ranked by how well each tank fits a real bed and a real fuel budget in 2026.
Table of Contents
Top 3 Best L-Shaped Transfer Tank Picks for 2026
UWS TT-75-COMBO 75 Gallon…
- 75 gallon L-shape
- Integrated chest toolbox
- Aluminum body
- 135 pounds
Dee Zee DZ92647B 92 Gallon…
- 92 gallon capacity
- Integrated toolbox
- .125 Brite-Tread aluminum
- 138 pounds
All 10 L-Shaped Transfer Tanks Compared (September 2026)
| Product | Specs | Action |
|---|---|---|
| UWS TT-75-COMBO 75 Gallon Combo L-Shaped Transfer Tank and Chest |
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Check Latest Price |
| RDS MFG INC Transfer L-Shape 95 Gallon |
|
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| Dee Zee DZ92647B 92 Gallon Aluminum Combo Transfer Tank and Tool Box |
|
Check Latest Price |
 UWS L-Shape Transfer Tank 100 Gallon Black |
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 Dee Zee DZ91754SB 50 Gallon L-Shape Transfer Tank Black Steel |
|
Check Latest Price |
 Dee Zee DZ92756SB 111 Gallon L-Shape Transfer Tank Black Steel |
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Check Latest Price |
 Weather Guard Transfer Tank L-Shape 90 Gallon Black Alloy Steel |
|
Check Latest Price |
 UWS Hammerhead Style Aluminum L-Shape Transfer Tank 100 Gallon |
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Check Latest Price |
 Aluminum Tank Industries TTL100 100 Gallon L-Shape Refueling Tank |
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Check Latest Price |
 RDS MFG INC L Shaped Auxiliary Transfer Fuel Tank 95 Gallon |
|
Check Latest Price |
1. UWS TT-75-COMBO 75 Gallon Combo Tank and Chest: Best Overall L-Shaped Transfer Tank
UWS TT-75-COMBO 75 Gallon Combo L-Shaped Transfer Tank and Chest
75 gallon
Aluminum body
Chest toolbox
135 pounds
49 x 27.5 x 24.5 in
Pros
- Aluminum body resists corrosion from harsh chemicals
- Integrated chest toolbox adds secure storage
- Reported to fit common half-ton pickup beds
- Four mounting tabs for removal and refitting
- Locking mechanisms work smoothly
Cons
- Toolbox side panels flex under pressure
- Some mounting tabs arrive bent or too short for the bed rail
- Actual capacity runs just under the nominal 75 gallons
This is the unit we kept coming back to while working through the list. Seventy-five gallons in a 49 by 27.5 by 24.5 inch footprint at 135 pounds empty is a genuinely balanced package, and the bolted-on chest means you are not giving up the whole bed to carry fuel. Owners on half-ton trucks, including a reported 6.5 foot Ram bed, say it drops in and stays put without any cutting or fabrication.
The aluminum body is the reason we trust it long term. Aluminum does not pit the way a steel tank can from the inside when a diesel tank sits half empty for a season, and it will not rust from a spilled gallon of diesel on the bed floor. At 135 pounds it is still a two-person lift, but it is well short of the 190-plus pound steel units later in this list.
The honest criticisms are all about the toolbox rather than the tank. Owners describe the side and vertical panels as thin sheet metal that flexes when you lean on it, and some report the chest arrived welded on crooked. A few also mention finding weld splatter in the fill connection threads that needs cleaning before a pump fitting will seat properly.
Check these details before you buy
Measure your bed rail height against the 24.5 inch overall height, and then add the pump. A 12V transfer pump typically sits well above the tank top once it is mounted, so the real clearance number you need is the rail height minus the tank height, not the tank height alone. Our fuel transfer pump guide covers flow rate choices if you have not picked one yet.
Ask about the mounting tabs. These are the part most likely to arrive bent, and a tab that is too short to reach the bed rail means the tank rocks under load. The multi-tab pattern here is a plus because you can remove the unit for winter storage and refit it without relocating anything.
Who this tank suits and who it will frustrate
Buy this one if you want a single unit that does fuel and storage, if your bed is a standard half-ton length, and if diesel is your fuel. It is the pick for landscapers and contractors who carry tools and fuel in one trip rather than making two.
Skip it if you need more than 75 gallons between fills, if your work is purely fuel with no gear to store, or if you plan to run a low-profile tonneau over the bed, because the chest raises the profile. Also expect a capacity a touch below the nameplate figure, which owners consistently note.
2. RDS Manufacturing 95 Gallon Transfer L-Shape: Best for High Capacity
RDS MFG INC Transfer L-Shape 95Gal
95 gallon
Aluminum
Silver finish
180 pounds
33 W x 52 H in
Pros
- 95 gallon capacity in a true L-shape footprint
- Aluminum construction carries a manufacturer warranty
- Silver finish suits most bed rails
- Two thirds of ratings are five star
Cons
- 180 pound build makes installation a two-person job
- Small review sample limits long-term detail
Ninety-five gallons is where the L-shape format starts to pay for itself, and the RDS unit is the cleanest example in this group. With roughly two thirds of its ratings at five stars, the owner feedback is unusually clean, and the listing carries a manufacturer warranty, which not every tank in this category does.
The aluminum construction is the practical draw. Diesel weighs in the neighborhood of 8.3 pounds per gallon, so a full 95 gallon tank puts close to 800 pounds on your bed, and that weight is easier on your payload rating and your hitch when the tank itself is not adding to it. The silver finish is also the least conspicuous option here if you care about how the bed looks when the tailgate is down.
What to watch before ordering
The listed dimensions come as 33 inches wide by 52 inches tall, which is a tall, narrow profile rather than a squat rectangle. That 52 inch height is the number that decides whether it clears your bed rails and whether it fits under a tonneau. Measure twice here.
Also budget for the load. At 180 pounds empty, you will want a second pair of hands and a set of ramps or a lift gate. Plan your mounting hardware and strap-down approach before the tank arrives, because a full tank that shifts under braking is the real risk, not the weight itself.
Who should buy this tank
This is the right pick for a contractor or ranch operator refueling a skid steer, a compact tractor, or a set of generators on site, where 75 gallons means too many round trips. If your equipment burns through fuel faster than you can realistically drive back to a station, capacity is the whole decision.
It is the wrong pick for a short bed, for a light-duty truck with a modest payload rating, or for anyone who wants a tank they can lift solo into the bed. Check your doorjamb GVWR sticker and subtract curb weight before this one goes in.
3. Dee Zee DZ92647B 92 Gallon Black Aluminum Combo Tank and Toolbox: Best Toolbox Combo
Dee Zee DZ92647B Black (92 gallon) Black Aluminum Combo Transfer Tank & Tool Box
92 gallon
Brite-Tread aluminum
138 pounds
L 46.75 x W 32.75 x H 25.375 in
Pros
- Spacious integrated toolbox for real tool storage
- .125 Brite-Tread aluminum body
- Black powder coat finish
- Good fit reported in compatible truck beds
Cons
- One owner reports brackets snapping after extended road use
- Aluminum and steel variants offered so construction varies
This is the tank for people who would otherwise run a separate bed toolbox. The DZ92647B bolts a full-size tool box onto a 92 gallon L-shape tank, so the profile fills the wheel well corner and the box occupies the space a standalone box would have taken anyway. Buyers single out the storage volume as the standout feature.
Construction is .125 inch Brite-Tread aluminum under a black powder coat, weighing 138 pounds empty. The stepped diamond tread on the top surface is not decoration, it is a walking surface, and it is a reason the tank doubles as a step or a working platform on a job site. The listed footprint is 46.75 by 32.75 by 25.375 inches.
Decisions that matter here
Pick the construction deliberately. Dee Zee offers this model in both steel and aluminum, so the listing you land on is not necessarily the tank you get. If corrosion is your concern, aluminum. If dent resistance in a rough work bed is your concern, steel. Do not assume from the product page title alone.
One detailed owner report describes mounting brackets snapping after extended road use, which is worth taking seriously on any combo tank because vibration is constant. Inspect the brackets and the weld where they meet the tank within the return window, and check the hardware bag against the manual before the first fill.
Where it fits and where it does not
Pick this if you carry hand tools, wrenches, and consumables and you would rather have one unit than two. The combination is what earns it a place on this list, and the aluminum weight keeps the loaded bed manageable.
Pass if your storage needs are small, because you would be paying for a box you half fill, or if your bed is a short model with a tight bulkhead-to-wheel-well run. Confirm the 46.75 inch length clears from the bulkhead to the tailgate opening on your specific truck.
4. UWS 100 Gallon Black L-Shape Tank: Best Full-Size Steel Capacity
UWS L-Shape Transfer Tank 100 Gal Black
100 gallon
Steel with aluminum components
190 pounds
Black powder coat
Pros
- 100 gallon capacity with a built-in toolbox
- Patented Rigid Core foam-filled lid resists binding
- Black powder coat finish
- Regarded as an auxiliary diesel fuel tank
Cons
- 190 pounds is heavy for a bed mount
- L-shape depth may not clear shorter beds
Hundred gallons plus a toolbox in a steel body is a serious proposition for a diesel operator, and this is the UWS unit built for it. The distinguishing feature is the lid, which uses a patented Rigid Core foam-filled construction. Owners like it specifically because the lid does not bow, bind, or fail to latch after a season of sun and cold, which is the standard complaint against flat sheet steel lids.
At 190 pounds empty, this is one of the heavier units we looked at, and it is listed as steel with aluminum components. Once you fill it, the payload math gets serious fast. Diesel at about 8.3 pounds per gallon puts roughly 830 pounds of fuel in there, so plan for something over a ton of added bed weight before you put anything else in the truck.
What to check before the tank shows up
Confirm bed length first. The most common reservation in the reviews is that the depth of the L-shape does not clear shorter beds, and that is a fitment problem you cannot fix with an adapter. Measure from the bulkhead to the tailgate and compare against the published footprint.
Because the tank is rated as an auxiliary diesel fuel tank, check whether your truck is already plumbed for an auxiliary tank before you buy. If it is not, this unit works fine as a transfer tank with a pump, but it is not going to feed your truck tank on its own. That distinction trips up a lot of first-time buyers.
Who this tank suits
It fits operators who burn diesel faster than a single fill covers, who already own a crossover or saddle box they need to work around, and who want a lid that keeps sealing year after year. Owners consistently report the combination of capacity, storage, and lid durability as the reason they are happy.
It does not fit a short bed, a light-duty truck with limited payload, or anyone who plans to lift the tank solo. On a half-ton with a modest GVWR, a full 100 gallon steel tank is often more than the remaining payload allows. Check the doorjamb sticker.
5. Dee Zee DZ91754SB 50 Gallon Black Steel L-Shape: Best for Short Beds
Dee Zee DZ91754SB (50 gallon) L-Shape Transfer Tank – Black Steel
50 gallon
14-gauge steel
65 pounds
L 30 x W 30 x H 24 in
Pros
- Lightest unit in the group at 65 pounds
- 14-gauge heavy-duty steel body
- Textured black powder coat finish
- Radius curve removes weld pressure points
- Compact 30 by 30 inch footprint
Cons
- Smallest capacity here at 50 gallons
- Ratings cluster at 4.0 with some middling three-star feedback
Sixty-five pounds empty is less than half the weight of most tanks in this roundup, and that single number is why this one is worth a look. On a short bed or a light-duty truck where payload is the limiting factor, a 50 gallon steel L-shape gives you real fuel capacity for a fraction of the loaded weight of a 100 gallon unit. Fifty gallons of diesel is around 415 pounds, which most half-ton trucks can absorb comfortably.
The build is 14-gauge heavy-duty steel with a textured black powder coat, and the footprint is a compact 30 by 30 inches with a 24 inch height. Dee Zee uses a radius curve on the corner transitions, which spreads stress across the weld instead of concentrating it at a sharp interior corner, and that is a meaningful detail on a steel tank that will flex as you load and unload it.
Where the trade-off shows up
Fifty gallons is small by the standards of this list. If you are refueling a machine that works hard, you will be topping this up more often than the 90 and 100 gallon units, and more fill stops mean more time. That is the honest limit of the compact footprint.
The other consideration is internal rust on a steel tank. Owners of steel tanks commonly worry about the inside of the tank when it sits empty for months, and the practical habit is to keep steel tanks fuller than you think you need to, or to drain and dry them at season end. The powder coat protects the outside, not the inside.
Who should look at this tank
Pick the DZ91754SB if you have a short bed, a half-ton truck with a working payload limit, or you simply want a tank you can lift into the bed yourself and pull out for storage. It is also a good match for anyone who carries fuel for a small generator or a pair of lawn machines rather than heavy equipment.
Pass if your fuel consumption outruns a 50 gallon capacity between supply stops, or if you want the maximum gallon count possible from a bed. For volume, look up the list at the 95 and 100 gallon options.
6. Dee Zee DZ92756SB 111 Gallon Black Steel L-Shape: Best for Maximum Fuel Capacity
Dee Zee DZ92756SB (111 gallon) L-Shape Transfer Tank – Black Steel
111 gallon
14-gauge steel
188 pounds
L 56.25 x W 32.75 x H 25.375 in
Pros
- Largest capacity in the group at 111 gallons
- Three stability baffles plus a drain plug
- 14-gauge steel with protective powder coat
- No ratings below three stars in the review set
Cons
- 56.25 inch length section demands a long bed
- Only a handful of reviews for a long-term read
When the question is how much fuel you can get into a bed, this is the answer in our group at 111 gallons. Owners rate the capacity, the baffling, and the finish consistently well, and there are no low ratings in the review set. Three internal stability baffles plus a drain plug is exactly the arrangement you want for controlled transfer and for emptying the tank at the end of a season.
The construction is 14-gauge alloy steel with a corrosion-protective powder coat, weighing 188 pounds empty, with a listed footprint of 56.25 by 32.75 by 25.375 inches. This model also comes in white, which matters more than it sounds if you are working in dust or snow and want the tank visible.
The fitment problem is the deciding factor
That 56.25 inch length section is the whole story. It needs a genuinely long bed, and if your measurement from the bulkhead to the tailgate falls short of that number, this tank will not sit flat against the front of the bed. Measure the usable length, not the advertised bed length, because the tailgate opening and the bulkhead both eat into it.
Loaded, this tank is close to 1,100 pounds of fuel and hardware in your bed. Check the GVWR sticker on your doorjamb, subtract your curb weight and any passengers, and make sure the remaining payload covers the tank, the fuel, and the equipment you haul. This is the unit where people get into trouble by oversizing.
Who this tank is right for
Pick the DZ92756SB if you run a long bed, carry serious payload, and want to make as few supply runs as physically possible. One fill covering a full week of heavy equipment work is the use case this tank was sized for, and the baffle system makes it safe to drive that loaded.
Pass if your bed is short, your payload rating is modest, or you haul a fifth wheel where bed weight is already spoken for. With 188 pounds of empty tank and over 1,000 pounds of fuel, this is a long-bed truck accessory, not a short-bed one.
7. Weather Guard 90 Gallon Black Alloy Steel L-Shape: Best for Vibration Isolation
Weather Guard Transfer Tank L-Shape 90Gal Black, Alloy Steel
90 gallon
12-gauge alloy steel
196 pounds
Powder coat finish
Pros
- Heavy-duty 12-gauge alloy steel body
- Interior baffles reduce fuel sloshing
- Rubber isolation bushings damp road vibration
- 2-inch NPT port and 3/8-inch drain port
Cons
- Heaviest unit in the group at 196 pounds
- One owner reported a crack and a warranty dispute
The distinguishing feature on this Weather Guard tank is the rubber isolation bushings at the mounting points. Tanks that bolt rigidly to the bed send every expansion and contraction from road vibration straight into the welds, and isolating the tank interrupts that path, which is the spec we would weight most heavily for anyone driving loaded gravel roads to a job site.
It is also the heaviest unit in this roundup at 196 pounds empty, built from 12-gauge alloy steel with a powder coat finish. The 2-inch NPT pump connection and 3/8-inch drain port are both sensible sizing choices, meaning pump selection will not be a fight, and the listing describes a universal fit for full-size trucks running gull wing or saddle boxes.
Read the review count carefully
There are only four ratings behind this unit, so treat the owner feedback as directional rather than established. Three are positive on build and fit. The fourth describes a crack appearing after about a year and a disagreement with the manufacturer over the warranty, which is exactly the kind of claim you cannot evaluate properly with a sample that small.
Inspect the tank on arrival, photograph every weld seam and bracket, and keep those photos. If you find a bent tab, a cracked seam, or a missing bushing, deal with it inside the return window rather than hoping it settles.
Who should buy this one
Buy it if you drive rough roads with a heavy load, if you run full-size trucks with existing gull wing or saddle boxes, or if you value the 2-inch NPT connection for pump compatibility. The isolation bushings are a real engineering benefit, not a marketing line.
Pass if weight is the problem, because at 196 pounds empty and roughly 750 pounds of diesel, this is the heaviest empty configuration in the group. It also does not carry the review depth of the units in the top half of this list, so accept that tradeoff knowingly.
8. UWS Hammerhead 100 Gallon Aluminum L-Shape: Best Lightweight 100-Gallon Option
Hammerhead Style Aluminum L-Shape Transfer Tank, 100-Gallon
100 gallon
Aluminum
111 pounds
Gloss black powder coat
Pros
- Only 111 pounds for a 100-gallon aluminum L-shape
- Lockable commercial-grade vented cap
- Leaves room for a separate truck toolbox
- Gloss black powder coat finish
Cons
- No integrated toolbox so a separate box is needed
- Only three reviews for a long-term read
This is one of the better spec sheets in the roundup. One hundred gallons of aluminum capacity at 111 pounds empty is roughly 79 pounds lighter than the 190 pound steel unit with the same gallon count, and that difference is meaningful when your payload budget is already committed to a trailer or a fifth wheel.
It also carries a lockable commercial-grade vented cap with a reinforced collar, which is the detail that separates a tank you can leave on a job site overnight from one you cannot. Owners describe the build quality as solid and the fit as good, and because the L-shape leaves the corner open, you can still run a separate truck tool box alongside it if you need storage.
Plan the pump and the storage
Since there is no integrated toolbox, budget separately for a storage solution. That is not a criticism so much as a fact of the layout, and it is why the L-shape format is often paired with a separate box in the same bed. Measure the remaining bed length after the tank footprint before you buy anything else.
With only three reviews on file, this tank does not have a long-term reliability record you can lean on. That is the honest reason it sits at eight rather than higher despite a strong 4.7 average. If you buy it, inspect it on arrival with the same care you would apply to any tank.
Who this tank works for
Pick the Hammerhead if you want 100 gallon capacity and you care more about loaded weight than about built-in storage, or if you already own a bed box that pairs with it. The lockable vented cap and the gloss black finish also suit anyone storing fuel on a shared site or a farm with equipment on it around the clock.
Pass if you need the tank and the toolbox as one unit, or if you want the largest capacity available, since the 111 gallon Dee Zee holds more. As with any aluminum tank, plan to empty it rather than let diesel sit against bare aluminum for months at a time.
9. Aluminum Tank Industries TTL100 100 Gallon L-Shape Refueling Tank: Best for Universal Fit
Aluminum Tank Industries TTL100 L-Shape Refueling Tank – 100 Gallon Capacity
100 gallon
All-aluminum
146 pounds
64 x 48 x 33 in
Pros
- 100 gallon capacity in all-aluminum construction
- Universal fit for bus and truck applications
- Refueling-tank style certification
- Ranks among the top sellers in fuel transfer tanks
Cons
- Bulk shape uses bed space less efficiently than a true L-shape
- Only three reviews for a long-term read
Aluminum Tank Industries builds this one for a different job than a pickup bed. The TTL100 is listed with a universal fit for buses, trucks, and vans, which means it can go into a service van or a shuttle bus body as readily as a half-ton bed, and that versatility is the reason to consider it if your work is not strictly pickup-based.
Capacity is 100 gallons in an all-aluminum body weighing 146 pounds, with a listed size of 64 by 48 by 33 inches. That 33 inch height is the tallest in this roundup, and it decides on its own whether the tank fits under a bed rail, a box, or a cover on your particular vehicle.
Be honest about the shape
The body here is a bulky main shape rather than a deeply stepped corner design. It delivers its 100 gallons, but it does not wrap the wheel wells as efficiently as a true L-shape combo, so you may be giving up bed space a stepped tank would have kept. If bed space is the reason you are considering the L-shape format, that undercuts the idea.
Three reviews is a thin evidence base, so verify the specification sheet against your own measurements rather than trusting the universal label. Confirm the 48 inch width clears between your bed rails and the 64 inch length clears the usable bed depth.
Who should choose this tank
Pick the TTL100 if you are outfitting a van, a bus, or a non-standard body rather than a pickup, or if you need a large aluminum capacity in a single simple body with no separate toolbox. Aluminum construction also makes it the choice for anyone who stores fuel long-term and does not want to think about internal rust.
Pass if you specifically want a pickup bed L-shape that preserves cargo space behind the tank, because this bulk shape does not deliver that. For a true stepped corner design in a truck bed, the Dee Zee and UWS combos earlier in this list are the better fit.
10. RDS Manufacturing 95 Gallon Auxiliary L-Shape Tank: Best for Auxiliary Fueling
RDS MFG INC L Shaped Auxiliary Transfer Fuel Tank – 95 Gallon
95 gallon
Machined aluminum
48 x 32 x 26 in
Manufacturer warranty
Pros
- Every rating is five stars across eight reviews
- Machined aluminum built for auxiliary fueling
- Handles gasoline auxiliary fueling with an electric pump
- Manufacturer warranty included
Cons
- Vehicle-specific fit needs bed clearance confirmed
- Listed weight of 16 ounces looks inconsistent with a 95-gallon tank
This is the one on the list built and sold as a genuine auxiliary tank rather than a transfer-only unit, and that distinction matters more than any other single feature here. If your truck is already plumbed with an auxiliary fuel line, this is the tank designed to feed it, and the machined aluminum construction is finished to a tighter standard than a coated steel shell.
Owners report strong satisfaction, and every rating on the listing is five stars across eight reviews, with the small sample being the main caveat. The listed size is 48 by 32 by 26 inches, and the fit listing covers boat, car, truck, and motorcycle applications. Owners also note it supports gasoline auxiliary fueling when an electric pump siphons from the top, which is unusual flexibility for a 95 gallon bed tank.
Check the data before you rely on it
There is a genuine data problem on this listing that you should know about. The stated item weight is listed as 16 ounces, which cannot be right for a 95 gallon aluminum tank, so treat the shipping weight as unreliable and confirm the real weight with the manufacturer before you plan your payload.
Confirm the auxiliary connection path. Auxiliary tanks need a feed line plumbed to your truck, and that plumbing is a separate job with its own cost. If your truck is not already set up for it, this becomes a transfer tank like any other, and you should weigh a plumbed option against a simpler transfer unit.
Who this tank is for
Pick the RDS auxiliary unit if your truck is already plumbed for an auxiliary tank, if you want to extend your range with fuel you haul yourself, and if you work with a fuel mix that includes gasoline rather than diesel only. The manufacturer warranty is a plus on a category where coverage varies.
Pass if you are buying purely for on-site equipment refueling, because for that job a transfer tank with a pump mount is simpler and cheaper. Also verify the fit carefully, since the vehicle-specific listing needs bed clearance confirmed before you commit.
Why Transfer Tanks Are L-Shaped
An L-shaped transfer tank has a stepped profile that nests into the corner of a pickup bed and rises over the wheel wells, so you gain capacity where a rectangle tank would waste space and you keep usable bed room behind it. Rectangle tanks must clear the wheel wells entirely, which forces a choice between losing capacity and losing cargo space. The L-shape occupies the dead corner instead of ignoring it, which is also why it is the format that tucks under an existing crossover toolbox.
That geometry matters most in short beds. A tank that has to clear the wheel wells ends up narrow and short, while a stepped tank uses the same footprint for considerably more gallons. If your bed is tight, the shape is doing work that capacity alone cannot.
How to Choose the Best L-Shaped Transfer Tank
Choose in this order: measure the bed, check remaining payload, pick capacity, pick material, then confirm the fuel rating. Skipping the first two is how people end up with a tank they cannot install or cannot afford to fill. Here is the process we use.
Step 1, measure the bed. Record the usable length from the bulkhead to the tailgate opening, the width between the inner bed rails, and the height from the bed floor to the top of the rail. Do not use the advertised bed length, because the bulkhead and tailgate opening both reduce the space you actually have.
Step 2, check payload. Find the GVWR on the doorjamb sticker and subtract curb weight, passengers, and any trailer tongue weight. Diesel weighs about 8.3 pounds per gallon, so a 100 gallon tank is roughly 830 pounds of fuel before you count the tank, the pump, and the brackets.
Step 3, pick capacity. Match the tank to how much you burn between supply runs rather than to how much you could carry. Thirty to fifty gallons suits occasional work and light equipment, sixty to a hundred suits regular on-site fueling of machines, and a hundred plus suits heavy daily use where supply runs are the bottleneck.
Step 4, pick material. Aluminum resists corrosion and weighs less, which matters on short beds and light payload ratings. Steel is heavier but shrugs off dents and abuse. If you will store fuel for months, aluminum is the safer long-term choice.
Step 5, confirm the fuel rating and markings. Most of these tanks are sold for diesel and other non-flammable liquids. If you intend to carry gasoline, verify the tank carries a UL listing appropriate to your state before you fill it, and never assume a diesel-rated tank is legal for gas.
Pairing a pump is the last decision, and flow rate should roughly match how fast you want to fill. Our fluid transfer pump guide breaks down the options, and it is worth budgeting extra wire length because bundled pumps often come with short leads.
Will an L-Shaped Transfer Tank Fit Under a Tonneau Cover?
Yes, but only if the tank plus its pump stays under your cover’s lowest clearance, and most do not on a low-profile cover. A soft folding tonneau or a low hard roll-up typically gives you only a few inches above the bed rail, so a 24 to 26 inch tank height leaves almost no room, and a 33 inch tall body like the Aluminum Tank Industries unit will not clear at all.
The practical test is rail height minus tank height minus pump height. If you do not have a clear number above a few inches, a tonneau and an in-bed tank are not compatible choices on the same truck. Many owners who want both end up moving the tank to a flatbed, a service body, or a trailer.
One further point worth checking: a crossover or gull wing toolbox sitting over the bed usually sits higher than a tonneau, so a tank that will not clear the cover will often clear the box. That is the setup that makes the L-shape format work for so many owners.
Aluminum vs Steel L-Shaped Transfer Tanks
Aluminum wins on weight and corrosion resistance, steel wins on dent resistance and cost. That is the short version. On a short bed or a truck with limited payload, the 79 pound spread between a 111 pound aluminum 100-gallon tank and a 190 pound steel equivalent is often the deciding factor, because it also lowers the loaded weight and softens the hit your suspension takes.
Steel tanks built from 12 or 14 gauge alloy steel absorb a dropped tool or a shifting load without damage, and they are the traditional choice for work trucks. The tradeoff is internal rust. Owners of steel tanks consistently advise keeping them fuller than feels necessary or draining and drying them at season end, because the interior is bare metal and condensation does the damage.
Aluminum tanks hold their value better over time and need no rust protection, but the metal is softer, so expect cosmetic dings and be careful when hanging hardware off the walls. For most owner-operators, aluminum is the default in 2026, with steel earning its place on heavy-duty and abuse-prone work trucks.
DOT Rules, Gasoline, and the 119-Gallon Limit
Under 119 gallons, you are generally exempt from hazmat placarding, but the tank itself must still be a certified container. That threshold is the single most useful number in this category, because it is why a 111 gallon L-shape tank can be driven on public roads without placards while crossing that line changes the legal category entirely.
Regular gasoline is a different matter. Most transfer tanks in this category are built and sold for diesel and other non-flammable liquids, and carrying gasoline in a diesel-rated tank is a real legal and safety problem, not a technicality. If you need to move gasoline, buy a tank that is UL listed for flammable liquids in your state and confirm the marking on the tank body before you fill it.
Two more things to know. A transfer tank is for private property in most jurisdictions, while a refueling tank carries the certification needed to fuel someone else’s equipment for hire. And the listings here do not always make the distinction clear, so check whether a unit is transfer-only or auxiliary. Several owner reports in this category describe listings described as auxiliary tanks that were transfer-only, and that trap is worth knowing about before purchase.
Whatever the tank type, ground it properly. A ground strap between the tank and the truck frame, a properly rated fuse on the pump circuit, and an auto shutoff nozzle are cheap additions that prevent the most common failure modes when you are pumping fuel in the field.
What Owners Complain About Most
Shipping damage is the number one complaint across this entire category, and it is not tank-specific. Owners across brands report bent mounting brackets, dented corners, and crushed or warped lids arriving from the factory. Missing or incomplete hardware is the second pattern, including tanks that arrived with only one working bracket. The fix is the same for all of them, inspect everything within the return window.
Return shipping is expensive enough that inspection is worth the ten minutes it takes, and one owner in this category reported a four figure charge just to send a misdescribed tank back. Check the mount count, the hardware bag, the weld seams, and the lid latch before the first fill.
Two more recurring themes. Short power cables on bundled pumps force extra wiring, so plan on buying extra lead or a battery box to run the pump independently rather than off the truck battery. And review suppression is a real problem in this category, with some listings showing low averages that reflect how few negative ratings owners are allowed to post. Read the low-star reviews on any listing you are considering rather than trusting the headline average alone.
Frequently Asked Questions
Why are transfer tanks L-shaped?
An L-shaped transfer tank has a stepped profile that nests into the corner of a pickup bed and rides up over the wheel wells. That shape converts dead bed space into fuel capacity, so you get more gallons than a slim rectangle tank of the same footprint while keeping usable bed room behind it. It is also the format that tucks under an existing crossover toolbox.
What size L-shaped transfer tank do I need?
Match capacity to how much fuel you burn between supply runs. 30 to 50 gallons suits occasional work and small equipment, 60 to 100 gallons suits regular on-site refueling of machines like skid steers, and 100 gallons or more suits heavy daily use. Remember diesel weighs about 8.3 pounds per gallon, so check your remaining payload before going large.
Can you put regular gas in an L-shaped transfer tank?
Only if the tank is UL listed for flammable liquids in your state. Most transfer tanks in this category, including nearly all of the models in this roundup, are built for diesel and other non-flammable liquids. Carrying gasoline in a diesel-rated tank is a legal and safety problem, so verify the UL marking on the tank body before filling it.
Will an L-shaped transfer tank fit under a tonneau cover?
Usually not on a low-profile cover. A 24 to 26 inch tank height leaves little room under a low hard or soft tonneau once you add a mounted pump, and taller bodies will not clear at all. The same tank often fits under a crossover or gull wing toolbox, which sits higher than most covers.
Are transfer tanks DOT approved?
Under 119 gallons you are generally exempt from hazmat placarding, but the tank itself must still be a certified container. Tanks used commercially to refuel someone else’s equipment generally need refueling-tank certification, and gasoline requires a UL listing for flammable liquids. Verify the certification markings on the tank rather than relying on the product listing.
What is the best fuel transfer tank?
For most owners, the UWS TT-75-COMBO is the best overall L-shaped transfer tank because 75 gallons, an aluminum body, and an integrated chest toolbox balance capacity, weight, and storage in a half-ton bed. Operators who burn fuel faster should step up to a 95 or 100 gallon unit, and short-bed owners should look at the 50 gallon compact steel option instead.
Final Verdict on the Best L-Shaped Transfer Tanks in 2026
The UWS TT-75-COMBO is our pick for the best L shaped transfer tanks overall, because 75 gallons, an aluminum body, and a bolted-on chest toolbox in a 135 pound package is the combination most owners can actually install and live with. If you burn through fuel faster than 75 gallons covers, the RDS 95 gallon unit gives you the capacity with aluminum construction, and the Dee Zee DZ92647B is the better choice when your toolbox needs to be as roomy as the tank is big. Short beds and light payload ratings point to the 65 pound Dee Zee 50 gallon steel tank instead.
Whichever one you choose, measure the bed before you order, check your remaining payload with a full tank in it, and inspect the tank and its brackets the day it arrives. That last step catches the damage that causes the majority of returns in this category.