Are you skimping on servicing your tow vehicle?

ByRV DailyFebruary 24, 2020
Are you skimping on servicing your tow vehicle?

You might think you have your tow vehicle’s maintenance sorted, but do you? Here are the things you should know to ensure your tow rig stays reliable

There is one thing you rely on more than anything when caravan touring, and that’s your tow vehicle. If your vehicle breaks down on a transport stage, it’s more than just a showstopper. If the tow vehicle can’t be easily fixed, then getting a tow for both vehicle and van in the bush can be difficult and expensive.

One easy way to avoid the inconvenience and cost of a tow vehicle breakdown is to get your vehicle serviced properly. While it won’t guarantee absolute reliability out in the bush, at least you’ll have the peace of mind knowing that the vehicle is up to date with its maintenance – both scheduled and preventative – and therefore unlikely to go bang in the middle of nowhere.

But when talking about a tow vehicle what does ‘proper servicing’ mean?

First off, if you have just bought a brand-new vehicle to tow with, hold it right there – you may not be able to tow with it at all, for now. While a break-in period for most vehicles has long gone, most manufacturers do still stipulate that you should not tow with a new vehicle. The period varies, but it’s usually around 1000km to 2000km of driving in your new vehicle before the manufacturer says that you can hitch up and go.

A vehicle is put under much more stress when towing than not. Just about all moving parts in the vehicle are getting an extra workout compared with a vehicle that does not tow regularly. The engine and transmission will run hotter, the cooling system will be under more load and the brakes and suspension will get more of a workout. Basically, everything is working harder when heavy-duty towing.

A Brand New Tow Vehcle May Need To Be Run In Before Towing With It

Manufacturers accordingly recommend a shortened service interval for towing, under what many call ‘Severe conditions’. Severe conditions usually include driving your vehicle with a lot of stop-start city use, off-roading and towing where such conditions are a regular part of the vehicle’s use.

Often the routine fluid change intervals for a severe conditions maintenance schedule are halved — so for example, a routine 12-month/20,000km service interval is shortened to six months or 10,000km, whichever comes first when you’re doing a lot of towing.

While no manufacturer nominates exactly how much towing puts a vehicle into the severe conditions servicing category, it’s fair to say that if you only tow your small van 300km every Christmas and that’s it, then you probably don’t need to worry about shortened service intervals considering how little towing you actually do. However, if like most of us you’re into the caravanning lifestyle and the towing kilometre count runs into the thousands, then you should reduce service intervals to what is nominated under severe conditions.

More Regular Engine Oil Changes Are A Must If Towing Often


Basically, severe conditions servicing means that engine oil and oil filter are changed more often, but there are other components that should see a mechanic’s careful looking over more often too.

Many manufacturers don’t specify shortened brake fluid change intervals for severe conditions: for most, it’s a set two-year interval. However, some do say you should change the fluid before then, every 15,000km in some cases.

Brake Fluid Should Be Changed More Often In Some Tow Vehicles


If your vehicle manufacturer does not specify a towing brake fluid change interval and you do tow a lot in mountainous terrain, or your van has override brakes (which are not quite as efficient or easy on the tow vehicle as a well set-up electric brake system) then you should consider moving to a brake fluid change once a year rather than every two years.


Many automatic transmissions are supposedly sealed for life but follow that edict at your peril, especially if towing a lot. While not on some vehicle’s severe conditions maintenance schedule, a transmission fluid and filter change should occur at around every 40,000km to 60,000km when towing.

Diff Oils May Need Changing More Regularly If You Tow A Lot


Diff oils can also get more of a work-out when towing, so check with your vehicle manufacturer to see if the oil in front and rear diffs of your 4WD needs to be dropped more regularly with the amount of towing you do.


Of course, the service should include all typical checks such as the cooling system for any loss of coolant, power steering fluid for loss or leaks, drive belts for wear, inspection of tyres for irregular wear and brake pads and rotors for wear.

Holding off on replacing routine service parts such as brake rotors/pads or tyres because they still have a little life left in them is a false economy too. You may find that the increased wear rates during towing will mean that those parts will wear out exactly where you don’t want them to – on tour out on a highway far from home.

Tyres that are close to their treadwear limit pose another problem. Not only will they offer less wet-weather grip but they are more susceptible to punctures, especially if you’re taking dirt road detours on your trips.

Check Tow Bar Tension As Part Of Regular Maintenance


An item not often on the service menu that should be is the towbar and towing electrics. Manufacturers such as Toyota state that the towbar attachments bolts should be re-torqued 1000km after fitting, but you should still periodically check tension after that too, especially if you use a Weight Distribution Hitch, which adds immense loads to the towbar assembly.

The towbar attachment bolts should have a tension of around 100Nm but verify exactly how much tension your vehicle’s towbar bolts require with the manufacturer as each has different bolt torque specs. While you or your mechanic is checking towbar bolt tension, the towball itself should be checked so that it is not loose, and the trailer electrical plug should be checked for any loose wires or debris from off-roading and cleaned or repaired as necessary. The hitch securing pin and anti-rattle bolt should also be inspected for wear and operation – you do not want the split pin missing from your hitch securing pin, for example. Correct tow vehicle maintenance does add inconvenience and cost to tow vehicle ownership, but the payoff is knowing that your vehicle will operate correctly when you really need it to – when you’re out touring with your van.

Have you got any tips for servicing while travelling? Let us know here

Words and images Phil Lord.