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Fuel and range

How far does it go on what it carries, and what’s left at each stop? Range here comes from the fuel you actually have and the consumption you measured on your own truck, by road type. The factory EPA figure stays in its own box as a stock reference, never as your range.

How to use this 3 steps
  1. Pick your truck and yearIts factory tank and EPA record fill in where we have a sourced figure. Where we don’t, they say unknown and you type yours.
  2. Tell it what you carry and burnFuel in the tank and any cans, the reserve you keep, and fill-ups you measured on highway, dirt and trail. One step at a time; stop after any.
  3. Read range, route and weightRange to your reserve by road type, fuel left after each leg of a route, and what the fuel weighs as it burns off.

Nothing here is saved. The page reads your saved rig to pick the truck and never changes it. Copy the link to keep a plan.

Your truck

Pick your truck, then tell the page how much fuel it carries.

Fuel on board

1Tanks and cansHow much fuel is on the truckAdd

Capacity is what a tank or can holds; fuel is what’s in it now. An empty can adds capacity, not range. Unusable fuel is what stays in the tank where the pump can’t reach it. Leave it blank unless you’ve measured it: blank means unknown, not zero.

2Your reserveFuel you plan never to useAdd
gal

Your choice, kept on top of any unusable fuel. LRDT doesn’t recommend a number.

Counts unknown unusable fuel as zero so you can see the arithmetic. Every figure it produces is labeled nominal, and none of them is a validated usable range.

3What it burnsMeasured fill-ups by road typeAdd

Fill up, drive a stretch that’s typical of the road type, fill back to the same level and enter the distance and what the pump dispensed. Several fill-ups add up as total distance over total fuel. On bigger tires the odometer reads short; use GPS distance or put your correction below.

GPS or measured-course distance divided by what the odometer showed for the same drive. Odometer fill-ups without it count as estimates.

4Route legsDistance and road type, stop by stopAdd

Fuel stops are yours to enter and are never assumed open or stocked. Until you tick that you’ve confirmed a stop has fuel, every leg after it shows as unknown, with what it would be if the stop comes through.

5Weight and balanceWhere the fuel sitsAdd
lb

The truck’s weight before this trip’s fuel and cans: your scale ticket, or curb weight plus parts.

So the tank’s fuel isn’t counted twice. Many makers quote curb weight with a full tank, but the page doesn’t assume it: check how yours was weighed.

in

Center of gravity height Optional, needs a sourced baseline

Only with the baseline weight above, a CG height you can source, and a height for every tank and can that changes. Otherwise the page reports the change in weight and leaves CG unknown.

in
Fuel density Gasoline: 6.3 lb/gal, estimated

Gasoline uses fueleconomy.gov’s figure of about 6.3 pounds a gallon (EPA and DOE), an estimate rather than the density of what’s in your tank. No diesel figure is on file yet; type one from your fuel supplier to weigh diesel.

lb/gal
lb/gal
Where these numbers come from Sources, formulas, status labels

Nominal capacity isn’t what the pump can draw on a slope, and a gauge isn’t a measurement. Check the fuel you actually have before you commit to a remote stretch. Use at your own risk.

Range

By road type

Range assumes the conditions you measured in. Load, wind, sand, grade, altitude, idling and a heavy foot all change it. Use at your own risk.

Fuel weight

Static, level ground

Static weights on level ground. No slosh, no dynamic load transfer, no off-camber behavior, and no rollover or mounting approval. Use at your own risk.

Stock reference

EPA, factory truck

The EPA tests a stock truck on a dynamometer. Its figure isn’t a measurement of a lifted, loaded truck on bigger tires or off pavement, so the page never uses it for your range and never adjusts it for tires, gears, weight or a roof load.

Carrying fuel

Reminders
  • Mount it solid. A can or tank that shifts under braking is a projectile and a leak. Use mounts rated for the container, and check them after rough miles.
  • Right container, right fuel. Use cans made and marked for the fuel in them, in good condition, with seals that close. Never mix fuels in one supply.
  • Know the local rules. PHMSA treats private, noncommercial fuel carrying differently from commercial hazardous-materials transport, but other agencies, states, parks, tunnels and ferries can set their own limits.
  • We don’t certify it. LRDT doesn’t approve any auxiliary tank installation, can, mount or position as safe.

How the numbers work

Why doesn’t it use my EPA rating for range?

The EPA rating is for a stock truck on a test cycle. Bigger tires, gearing, a lift, bumpers and a roof load all change consumption, and they interact, so stacking a percentage for each one gives a confident number nobody measured. Range here comes from consumption you measured on your own truck. The EPA figure stays as a stock reference in its own box.

How do I measure my consumption?

Fill the tank, note the distance from GPS or a corrected odometer, drive a stretch that’s typical of one road type, then fill back to the same level and note what the pump dispensed. Distance divided by fuel is one measurement. With several, the page adds the distances and the fuel and divides the totals, which weighs a long trip more than a short one. A partial refill doesn’t count, because it doesn’t tell you what was burned.

What is unusable fuel, and why isn’t it zero?

Fuel that stays in the tank where the pump pickup can’t reach it, more of it on a steep slope or a side hill. Makers rarely publish it and the low-fuel light doesn’t measure it. Until you measure it, it’s unknown, and so is exact range to empty. You can ask for nominal arithmetic that counts it as zero; those figures are labeled nominal.

Reserve or unusable fuel?

Both, kept apart. Unusable fuel is physics: it can’t reach the engine. Your reserve is a choice: fuel you plan never to use. Range to reserve is current fuel minus unusable fuel minus reserve, divided by consumption, and never less than zero.

How does a fuel can count?

Only after you pour it in. Cans and switched auxiliary tanks show as extra range after transfer, never as fuel already in the tank. An empty can adds capacity, not range, and a can of the wrong fuel never counts as supply. On a route, put the transfer at the end of the leg where you’ll do it, and it only moves what fits in the tank.

What does the fuel do to the axles?

Fuel weighs density times volume; the page uses fueleconomy.gov’s 6.3 pounds a gallon for gasoline, an estimate. A weight m sitting x behind the front axle on a wheelbase L puts m times x over L on the rear axle and the rest on the front. Behind the rear axle that front share goes negative: it lifts weight off the front. Without a measured position for the tank or can, the page reports the change in total weight and leaves the axle change unknown.

Use at your own risk. These calculators are here to help you plan and to inform your decisions, not to sign off on a build. Many numbers are estimates worked out from factory figures, and some factory figures are not yet confirmed. Check every number against your own truck, its manuals and a qualified shop before you buy parts, cut, weld, lift, regear or drive on it. Long Range Desert Tools is not liable for anything you do based on these calculators or their results. The full terms are in our policies.