How much more fuel does towing a caravan use?

It depends on the vehicle, the caravan's weight and frontal area, speed, wind and terrain, so there's no single figure. A big, tall caravan at highway speed costs far more than a small camper trailer at 80 km/h. The most reliable number is your own: fill up, tow a few hundred kilometres, fill up again and divide the litres by the distance.

How do I work out my fuel use when towing?

Fill the tank to the brim, reset the trip meter, tow as normal, then fill to the brim again. Divide the litres you put in by the kilometres travelled and multiply by 100. That's your towing figure in litres per 100 km. Enter it as your usual figure with 0% extra, or compare it with your unhitched figure to get the percentage.

Why does my range drop so much when towing?

Range is your usable fuel divided by fuel use, so every extra litre per 100 km cuts it. If towing uses 50% more fuel, the same tank goes two thirds as far. Keeping a reserve for remote stretches shortens your planned range further.

Does towing slower save fuel?

Yes. Air resistance rises steeply with speed, and a caravan adds a lot of frontal area. Dropping your cruising speed is usually the biggest single fuel saving you control. In WA every vehicle towing is limited to 100 km/h anyway, and in NSW most ute and caravan setups are too.

Should I carry jerry cans for a long trip?

On remote routes, check the distance between fuel stops against your towing range, not your normal range. If the gap is close to your range, a long-range tank or jerry cans give you a margin, but fuel is heavy (diesel is about 0.84 kg per litre) and counts against your GVM.

Towing fuel consumption and range calculator

How it's worked out

Towing fuel use = usual L/100 km × (1 + extra % ÷ 100)Range per tank = (tank − reserve) ÷ towing fuel use × 100Trip fuel = distance × towing fuel use ÷ 100

The refuel count assumes you start with a full tank and refill whenever you reach your reserve.

Worked example

A ute that uses 11 L/100 km unhitched and 45% more when towing uses 11 × 1.45 = 15.95 L/100 km with the caravan on. With an 80 litre tank and a 10 litre reserve, 70 litres is usable, so the towing range is 70 ÷ 15.95 × 100 = about 439 km, compared with about 636 km unhitched. A 1,200 km trip takes about 191 litres, or about $392 at $2.05 a litre, and two refuels on the way.

Find your real towing figure

The extra percentage is the number most people guess, and it varies more than anything else here. Measure it on your next trip: fill to the brim, tow at least 300 km, fill again, then divide litres by kilometres and multiply by 100. Do it once on the highway and once on a hilly or windy day and you'll know your range on a bad day too.

Fuel weighs something too

A full tank and jerry cans add weight to the vehicle, and that weight counts against its GVM. Diesel is about 0.84 kg per litre and petrol about 0.74 kg per litre, so 40 litres of spare diesel adds about 34 kg. Check you still have room with the payload calculator.

Common questions

How much more fuel does towing a caravan use?: It depends on the vehicle, the caravan's weight and frontal area, speed, wind and terrain, so there's no single figure. A big, tall caravan at highway speed costs far more than a small camper trailer at 80 km/h. The most reliable number is your own: fill up, tow a few hundred kilometres, fill up again and divide the litres by the distance.
How do I work out my fuel use when towing?: Fill the tank to the brim, reset the trip meter, tow as normal, then fill to the brim again. Divide the litres you put in by the kilometres travelled and multiply by 100. That's your towing figure in litres per 100 km. Enter it as your usual figure with 0% extra, or compare it with your unhitched figure to get the percentage.
Why does my range drop so much when towing?: Range is your usable fuel divided by fuel use, so every extra litre per 100 km cuts it. If towing uses 50% more fuel, the same tank goes two thirds as far. Keeping a reserve for remote stretches shortens your planned range further.
Does towing slower save fuel?: Yes. Air resistance rises steeply with speed, and a caravan adds a lot of frontal area. Dropping your cruising speed is usually the biggest single fuel saving you control. In WA every vehicle towing is limited to 100 km/h anyway, and in NSW most ute and caravan setups are too.
Should I carry jerry cans for a long trip?: On remote routes, check the distance between fuel stops against your towing range, not your normal range. If the gap is close to your range, a long-range tank or jerry cans give you a margin, but fuel is heavy (diesel is about 0.84 kg per litre) and counts against your GVM.