I’ve long thought rust was a thing of the past. Rust prevention technology has gotten so good that I haven’t had a car with a rust problem since a decade-old 1985 Ford Escort. And even with the Escort rust wasn’t externally visible. I hardly ever see a car with visible rust around the Detroit suburbs, and those I do see are over a decade old.

Then a few months back I noticed that my 2003 Mazda Protege5 was rusting around the rear wheel openings and along the inside of the driver’s door, where the inner and outer panel are welded together.

Conducting the TrueDelta Car Reliability Survey, I’ve been receiving multiple reports of such rust with both the Protege and the Mazda3. As far as I can tell, neither model has sufficient rust protection for areas where the roads are salted. In some cases, rust has started within the warranty period.

People still remember how Hondas used to rust back in the 1970s and 1980s.

Now I’m wondering if Mazda’s rep is going to take a similar hit. Rust is worse than other problems–you can’t fix it merely by swapping out parts. It’s essentially cancer for cars. I’ve treated those areas I can get to, and repainted them. But this will probably be an annual procedure going forward. A shame, because these particular models are otherwise very durable.

The rust warranty lasts for five years–so it ended a year ago today for me. Called the dealer I bought the car from, and they essentially said I’m SOL. Especially since I haven’t been taking the car there for $30+ oil changes.

Which is about what I expected. Another thing I’ve learned by conducting this survey: with nearly all manufacturers, when the warranty is over, it’s over, even if an obvious engineering or manufacturing error is causing a widespread premature problem. You do get some chance of out-of-warranty assistance if you go to the dealer for all of your service–but I haven’t quite learned this lesson yet.

Would I have bought this car if I’d known it’d be rusting out within six years? As much as I like it, probably not.