Rust-proofing your rig

By: Claire Wilson, Photography by: Offroad Images

Rust is an ever-present threat to your car and camper, but there’s plenty you can do to stem its advance.

Rust-proofing your rig
Ignore the threat posed by rust at your peril...

There's nothing worse than having a rusty vehicle. Not only is rust time consuming to fix, it also weakens your rig's structural integrity and lowers its resale value. Driving on the beach is a sure-fire way to encourage rust, as the salty environment speeds up corrosion - especially in nooks and crannies where sand or water can become trapped. Of course, avoiding environments like the beach will go a long way towards rustproofing your car and camper, but then that also defeats the purpose for which you bought the latter in the first place - enjoying our great Australian outdoors.

Steel corrodes when it's exposed to oxygen and water, because a chemical reaction occurs between the three that leads to the formation of iron oxide - the reddish brown stuff we commonly refer to as rust.

So, the term 'rustproofing' is actually a bit of a misnomer, as the truth is that no matter what you do, it's inevitable that your vehicle's metal components will rust. We can only make an effort to slow the process by limiting our vehicle's exposure to oxygen and water.

Having said that, modern vehicles (that is, anything built after around 1980) make use of manufacturing methods that maximise a car's ability to resist rust with things like galvanisation, PVC-based undercoats, and modern paint technologies. Many cars now even come with a 10 year guarantee against rust, regardless of the maintenance they receive, so it logically follows that, with good maintenance, these days your car will remain rust free for much longer.

Camper trailers are often made from materials that are rust resistant, like aluminium or even fibreglass. But not all trailers are and their fixtures and fittings generally aren't, along with the drawbars and chassis - so maintenance to ensure rust prevention is essential.


The single most important aspect of maintaining a car or camper trailer rust-free is ensuring you wash it down thoroughly after every single time it's exposed to a salty environment. Pay particular attention to areas where sand and water may pool, such as the underbody, and any hidden crevices particular to your vehicle. Give the engine a rinse (after it's cooled down sufficiently) and don't forget the roof, as this is a vulnerable area for many cars.

After washing take the car for a spin to dislodge any sitting water, then visually inspect and dry with a cloth any regions that you think may still be wet. If you don't get the opportunity to hook the trailer up for a drive then let it dry in the sun and have a look to see if water has pooled anywhere - if it has, dry it off with a cloth.

Of course, if there is a freshwater river crossing on the way home from the beach, just take the detour and it will rinse your undercarriage for you.

Even if you haven't been beach driving, clean the car thoroughly every two weeks, and the camper trailer whenever you get home from a trip, to get rid of any animal or plant materials that can damage your vehicle's protective clear coat.


Any damage to your car's or camper trailer's paintwork should be repaired as soon as possible. Stone chips and scrapes expose the vulnerable steel panelling, which encourages the development of rust.

We all try to avoid damaging our car and trailer, but if it does happen ensure you get it repaired as soon as possible.


There are myriad different surface treatments available to protect against rust.

These are intended to treat not only the exterior of the car, but also the inside of the panels, behind door dressings and so forth. Application therefore requires a certain degree of mechanical nous, which is why the service is offered by many professional car repair centres.

All the surface treatments available are based on the same theory - they are an additional protective layer to protect the metal from exposure to oxygen and water.

Fish oil is the old school classic in rust prevention, but it does tend to leave your car with a sharp pong for a week or so (some say months) after application. Lanolin is another alternative but it's water soluble, so it won't last nearly as long. Things also stick to lanolin, but it's still a very popular underbody treatment before a spot of beach driving.

There are also wax-based treatments, such as Valvoline's Tectyl, which last for up to five years.

The effectiveness of these treatments depends entirely upon the quality of the application, and the only way to be sure of that is to do it yourself. If you are uncertain about whether you would be able to get the interior door trimmings back on then it is probably best to leave it up to a paid technician. In this case ask around for recommendations from any friend who had their older car rustproofed a number of years ago - and who still hasn't experienced any rust trouble.

These treatments do need to be maintained, but stay on top of them and they'll only extend your rig's life.


Electronic rust prevention systems (ERPS) are controversial products in the rustproofing world. They are relatively expensive, generally costing upwards of $500, and rely upon testimonials to prove their effectiveness.

Some swear by them, although they do involve a leap of faith, but there is a strong argument for their use: their cost pales into insignificance when you consider they're offering potential protection for a $40k+ investment like a fourbie.

Power is supplied to the ERPS unit from the car's battery and sent via wires to a number of couplers (anywhere between one and 10) located at various points around the vehicle. The theory is that a negative charge is created on the vehicle's metal surface, with the car's paint holding the charge static. The idea is that the capacitor works to constantly replace lost electrons on the vehicle's body, preventing rust.

Ultimately, with an unproven system like this you pay your money and you take your chances.

Source: Camper Trailer Australia #42