Hello all, I recently purchased a 2011 RAV4 with under 100K miles and it runs great, however, there is some rust on the undercarriage. I was just wondering if I should be worried?

 

That's minimal surface rust really. If you are concerned though you could tend to the control arms and frame welds (middle pic). I wire brush then apply a spray made with tannic acid that turns the rust into a black primer (Dupli-Color Rust Fix). If you decide to undercoat though, DO NOT use a thick rubberized material that has no rust inhibitors and isn't breathable, particularly Ziebart. All that dose is trap in rust and moisture and make the problem worse.

There's a couple breathable ones I know of, Krown (mostly available in Canada), and Fluid Film. I don't know a whole lot about Krown, but Fluid Film is a material that never dries out and immediately stops rust from spreading, but it's recommended to reapply it once a year. I had my 82 toyota pickup undercoated by a detail shop that uses a tar-like material that has rust inhibitors in it.

If you use Rust Fix, make sure you do not wire brush down to bare metal. Proper prep is to leave a very fine surface layer of rust after the scaling and heavy surface rust are brushed out. It needs that fine layer of surface rust present to convert it into the black primer.

BTW, I'm heading out tomorrow to look at a 1998 RAV 4 with 120,000 mi on it. Body and paint are dent and scratch free, and he says underneath looks good too. It does need new shifter cables though, and those can get expensive to have installed where I live. I hope it's good enough to buy, because my truck just got stolen.

 

Don't worry about it. It's normal for a used car. It shouldn't affect the car in anyway. But if you don't feel comfortable with it, you can spray it

 

What part of the country are you in? That looks pretty clean. Get it undercoated and keep putting the miles on it.

 

Real old thread, but for a New England car that would be excellent. Massachusetts uses at least 4 different car-eating concoctions on the roads in winter.