How to look for a fuel-efficient tow vehicle

When you think about it, using a car or four-wheel drive to tow a trailer much bigger than a standard box trailer is really asking a lot of the car’s design and engineering. 

For a start, you’re potentially doubling (or more!) the mass of the tow-vehicle once it’s all coupled up. That obviously places strains on everything from the tow-hitch itself to the mounting point on the car, not to mention the extra load on the springs, suspension arms, bushes and bearings.

Then consider how much harder the car’s driveline has to work. Hauling all that extra weight from a standing start, up a hill on a 40-degree day is a huge ask. Simple physics sees to that. 

And it’s not just the engine that can struggle; the transmission also cops a workout in the above example, as do the driveshafts and differentials and anything else that has to turn, flex or rotate to make that happen. And that’s before we get to stopping it all at the next red light. Spare a thought for those brakes…

In the past, the solution has been to buy more tow vehicle than you thought you’d need and allow for that extra cooling, engine capacity, braking and heavy-duty suspension to give you some engineering headroom. 

But these days, with the cost of fuel at an all-time high, many folks who need to tow caravans, boats or whatever, are seeking out more economical vehicles for this task.

In a way, it’s asking for trouble, but it’s also true that modern vehicle design means cars and four-wheel drives can do more with less. So, sticking vehicles that are designed with at least some towing in mind (nearly any car can be a tow car if it can be physically fitted with a tow-bar) what are the most economical vehicles to use to shift a load from A to B?

In a general sense, the old rules still apply. That starts with engine choice and the default setting really is a diesel. Diesels inherently squeeze more from a litre of fuel than a petrol engine. And modern turbo-diesels are absolutely brilliant at this, as well as offering great torque characteristics spot on for hauling a load away from rest.

Diesel engines are best suited for towing. (Image: Glen Sullivan).

Modern diesels build turbo-boost so quickly and early in the rev range that they’re boosting up almost from idle. This means they get into a big pile of Newton-metres fast, and it’s torque – not horsepower – that gets heavy things moving.

Yes, a turbo-diesel can be a bit more expensive to maintain with extra servicing and sometimes attention required to things like the particulate filter and injection system, but if you’re a regular tower, the fuel-consumption advantage will probably win out over time.

The second thing that hasn’t changed is the choice of transmission. CVTs might be super economical, dual-clutches great on a race-track and old-school manuals fun, but for towing efficiency and longevity, you just can’t beat a conventional automatic with a torque converter design. 

Not only does the automatic take up the weight of the load more progressively, the way the torque converter allows some slip means you won’t be roasting clutches or internal bits. The two-pedal operation also means one less thing to distract you when attempting to reverse a trailer through a narrow gate.

A regular torque converter auto doesn't risk burning the car's clutch when towing.

Modern automatics also feature coolers which is a great thing because as any automatic transmission specialist will tell you, you can’t over-cool an automatic. 

In fact, those that frequently tow big loads, often fit an aftermarket transmission cooler. In the past, carmakers would also offer a towing pack which featured a bigger cooler, but that isn’t something being offered these days.

Since so many tow-cars these days are SUVs, there’s also the option of all-wheel drive to consider. Fundamentally, an all-wheel drive vehicle makes a much better tow car than a front-wheel drive one.

Rear-drive also works pretty well, but these days, it’s usually a choice of FWD or AWD, so we’d take the latter every time. 

Most tow vehicles are SUVs and are all-wheel-drive. (image credit: Glen Sullivan)

Essentially, by splitting the drive across four tyres rather than just two, you greatly increase your chances of getting a heavy load moving without wheel slip. 

Anybody who has launched a boat from a wet, slimy council-ramp will know what we mean here. And when it comes to parking a caravan on a grassed site, having all-wheel drive is like a gift from the traction gods. 

And again, you’re splitting the stresses across four driveshafts rather than two, and that’s got to be good for long-term durability and running costs.

Popular types of tow-vehicle right now include those SUVs we mentioned as well as conventional, off-road four-wheel drives. 

While the latter are supreme tow cars with their ladder-chassis construction and heavy-duty all-wheel drive drivelines, they’re not going to be the most economical tow rigs out there. Their huge weight and blunt aerodynamic shapes see to that, and many caravanners, for instance, have discovered the dual-cab ute as a towing solution.

Dual-cab utes have become a popular option for towing.

These often have huge legal towing ratings and quite economical turbo-diesel engines, although the vehicle that uses the least fuel on its own may, in fact, become one of the thirstier models when hooked up to a 2.0-tonne caravan. 

Most dual-cab utes also have conventional automatic transmissions and are available as all-wheel drives, making them spot on for the job.

The other alternative is a medium or full-sized SUV with the option of AWD and a diesel driveline. There are also plenty of these around, the only catch being that some aren’t rated for high loads. 

Utes usually have large legal towing ratings and quite economical turbo diesels. (Image: Sam Rawlings)

There’s also the fact that to get the AWD diesel driveline with the automatic transmission, you have to spend up big and go for a top-of-the-line model rather than the entry-level version which might have a petrol engine and front-wheel drive.

It's also important that you buy a reliable make and model. Towing a caravan on your big lap of Australia is not the time to be doing market research into what makes and models give trouble under such conditions. 

Choose a known brand with a good reputation and be aware that finding a dealer or parts supplier in remote parts of the country can be very difficult with some brands.

Be aware also that no matter how economical the car was without the trailer hooked up, it will still use a lot more fuel when towing and will need to be serviced and maintained meticulously.