How to fit a towbar

As a caravanner, you’re not going to get very far if your vehicle isn't fitted with a towbar and trailer wiring.

Fitting one yourself is a relatively easy job to do, provided you’re familiar with the tools and have an appropriate dry, well-lit place to do the installation.

This is just a general guide to towbar fitment; it's no substitute for instructions specific for your vehicle. Every tow vehicle is different, and so while what we’re showing you here will give an idea of what's involved, it will not necessarily be exactly the same steps as required for your vehicle.

Do your towbar research

Before you buy a towbar, it’s important to do some research on the towing specifications for your vehicle.

Make sure that the towbar and the vehicle manufacturer’s maximum towing specs match. You may also have to fit other components, such as an automatic transmission cooler, to meet the vehicle manufacturer’s requirements for towing.

There are rules governing towbars. Australian Design Rule (ADR) 62 became effective in July 1991, and this ADR is a combination of Australian Standards developed over the years and refines the requirements and testing of towing equipment such as towbars.

Under ADR 62, all new towbars have to comply with the strength, function and identification requirements. The ADR lists static and dynamic forces that the towbar must be able to withstand.

The towbar must sit at a certain height, too. The height to the centre of the ball determined when laden must be between 350 and 420 mm.

The towbar must be fitted with two safety chain attachment points, mounted either side of and adjacent to, the tow ball mount, although only use of one safety chain is required when towing up to 2500kg.

The ADR also requires that the towbar be marked with the following identification: the towbar manufacturer’s name or trademark; and the maximum allowable trailer aggregate tare mass and its units of measurement in kilograms for an ATM up to 750 kg or in tonnes otherwise, at which the towbar is rated and identify what model the towbar is designed to fit.

The Australian Standard for towballs is a 50mm diameter, and the rating of the towball has to be stamped on the ball.

Though it's rare to see on newer vehicles, if the ball mount tongue obscures the number plate it must be removed when driving without a trailer attached.

You’ll note that this Range Rover already had a towbar fitted; however, it was a New Zealand-market towbar, with just a 150kg TBM rating. To be absolutely sure that the towbar met ADR 62 Australian compliance requirements and to benefit from an increased TBM permitted with an Australian-spec towbar, we replaced it with a local, ADR-approved unit.

Let’s get started

First, assemble the towbar kit and tools required. Make sure all the nuts and bolts and everything else that is in the kit is actually there -- it’s a bit rough to find out that the kit is short one bolt when you’re half way though the install.

If you don’t have a ‘tools required’ list supplied with your towbar, then you will at least need a socket set, screwdrivers (Philips head and flat) of various sizes and shank length, a torque wrench and a tape measure.

Additional cable ties to tidy up wiring and a rotary cutting tool or hacksaw and a length of pinchweld to neaten-up the bumper aperture (if you need to cut it to fit the towbar) may also be required.

Disconnect the vehicle battery (as you’ll be plugging in a new loom) and remove any components required at the rear of the vehicle necessary for access while fitting towbar.

You may need to remove taillights, rear bumper bar and bumper supports. Here we just needed to disconnect parking sensors, mudflaps, inner guard extensions and the rear bumper itself.

While it was unnecessary for this install, you may also need to remove a foam bumper support, cut or modify other components (such as an exhaust shield for example) and cut the (ABS plastic) bumper to allow the towbar to fit.

Most towbar kits will have a template to use for cutting the bumper - make sure to measure and re-check measurements before starting cutting.

Cut the plastic bumper with either a small rotary cutting tool or hand cutting with a fine blade hacksaw (which is time-consuming but you’re less likely to make a mistake).

If you're not entirely happy with the result, buy some automotive pinch weld and fit to the bumper cut out - it’ll look a lot neater.

Get a helper if needed

Fit the towbar up to the vehicle and fit mounting bolts and torque to specifications.

While this can be done solo, sometimes it is a lot easier with a helper as towbars are typically 20kg-plus.

Wire up the trailer connection, which in most cases will be a simple job with the loom supplied with the towbar kit.

If no loom is supplied, then you’ll need to get a hold of 4mm gauge insulated copper wire and clip connectors.

Some modern vehicles require a dedicated loom though because if you tap into the taillight connections - as is possible with older vehicles - the newer vehicles will sense the current drain and declare it as a fault.

Refit the bumper and other components removed prior to bar fitment and re-torque to manufacturer’s specifications.

Now make sure that the trailer plug is attached to either a dedicated spot on the towbar or onto the rear bumper.

Now  attach the tow tongue, securing it with the pin and circlip  and if fitted, tightening the anti-rattle bolt.

Then bolt up the towball, making sure you’ve fitted the split washer and torqued up the towball to specs.

Use a few layers of tape if required to ensure you don’t damage the surfaces of your shiny new towbar and towball when tightening.

Final bits and pieces

Test the trailer connector ports to ensure they are receiving voltage and lastly, fit the towbar compliance sticker to a easily seen section of the inner driver’s door or door jamb.

Related reading:

DIY Redarc brake controller fitting

How to fit a caravan mover