When to stop worrying about rust on cars?

[human]

We have a 2002 civic, for most of its life it was parked indoors. We got a second new civic 2 years ago (paid off already) and now the old one sits outside overnight and has done so for the last two winters. We didn't do a rust proof undercoating last year, I don't know if those even work. My SOs parents at one point insisted we get some minor rust taken off, we took it in and I'm convinced they just painted over a few spots. The old car will sit outside again this winter, I've noticed some rust around the wheel wells/ fenders whachamacallits, we live in Ottawa so lots of ice, snow and salt.

How long can this thing last without bothering to do something about rust on the body panels? The car has been in an accident (fixed by insurance) so I'm not to concerned about resale, it doesn't even have 100,000 miles on it but the age and accident would probably bring the resale to less than 5k I'm guessing.

I'm torn, just got the timing belt changed this summer and transmission fluids, new tires (rated for 60,000 miles) two years ago. That all cost money but for some reason I don't want to shell out for rust proofing or fixing existing rust. When did you guys decide to just let your car fall apart? Thoughts and comments appreciated.

[Yonco]

Brake lines are the first things to rust through, ive driven a few vehicles with rusted rockers and wheel wells, but its always a bad day when you have to use the curb and a right turn to stop your car. So check your brake lines, those will go first!

[human]

I'll have to check but I think some pads were replaced recently, not sure of the lines though.

[gooki]

They do not salt the roads down here, but when we purchased our 1998 nissan there was a spot of rust on the bonnet. 8 years later, having never been garaged the spot of rust is only 30% bigger. So glad I didn't waste money having it repaired.

Id only got fixing rust where you notice it's increasing in size. And rust on any mechanical parts.

[lakemom]

As long as it doesn't affect the function of the car, I'd totally ignore it.  Rust (until it gets really bad) is a cosmetic issue not a function/safety issue.  I'm fairly certain that once rust has begun rustproofing isn't possible.  Google around on ways to stop/slow down rust on an older car and do that. 

[Emg03063]

Back when auto bodies were metal, this was a concern, but not in the last 20 years or so.  Go to the carwash in the spring, wash the salt off the undercarriage, and call it good.  If you're really concerned about it, hit it with a wire brush and some marine paint.  Total cost <$10.

[wtjbatman]

Back when auto bodies were metal, this was a concern, but not in the last 20 years or so.  Go to the carwash in the spring, wash the salt off the undercarriage, and call it good.  If you're really concerned about it, hit it with a wire brush and some marine paint.  Total cost <$10.

The exhaust on my 2004 rusted out. It took being parked outside and used as a daily commuter for ten Minnesota winters.

It's not just the cosmetic parts you can see.

[Civex]

Also in Minnesota- car has seen roughly 12 years of MN salt and when I asked an auto body repairman if there was anyway to stop the rust in my rear quarter panels and hatchback he recommended soaking them with WD40. As far as when to worry, if you take your car in for oil changes or tire rotations, ask the technician to look over the brakes/suspension-they should be able to let you know when something needs to be replaced due to corrosion. Working in a poorer area, I see cars daily that seem to missing the 8-12" closest to the ground due to rust, so you probably don't need to worry.

[daverobev]

Out in the Ottawa cold is fine. It doesn't rust when its cold - needs liquid water. Going into a heated garage is much worse.

2002 Civic, if there are no real rusty bits already you're good for the life of the car. Undercoat every other year with Krown or whatever.

We had an 04 Civic that was in much better shape than the 02 Accord that replaced it. The Accord is rusting in places but will still last a year or two more (probably more but whatever).

Pics of the rust?

[Bob W]

I would not be concerned about the cosmetic rust.  My 1999 Mountaineer has some rust spots.   The value of you vehicle will go down each year and spending thousands to address cosmetic rust is not a good investment.   At your current driving rate you may have this car for another 15 years.   It will be worth close to zero by then regardless of the rust condition. 

Just keep and eye on it.   

[JLee]

Back when auto bodies were metal, this was a concern, but not in the last 20 years or so.  Go to the carwash in the spring, wash the salt off the undercarriage, and call it good.  If you're really concerned about it, hit it with a wire brush and some marine paint.  Total cost <$10.

What exactly are they made of these days, then? :P

[Exflyboy]

The bottom line is, if you live where they salt the roads and you drive your car in Winter.. your car will rust.. If you live where they don't salt it won't.

I just scrapped '97 Neon with not one spec of rust anywhere for that reason.

The problem is not limited to the under carriage, the salt water spray gets between the seams.. you can't wash that out no matter how hard you try.

Personally I'd buy my cars from Oregon then drive them back to your "rusty State".. At least you'll be starting with a rust free car.

[The_Dude]

Back when auto bodies were metal, this was a concern, but not in the last 20 years or so.  Go to the carwash in the spring, wash the salt off the undercarriage, and call it good.  If you're really concerned about it, hit it with a wire brush and some marine paint.  Total cost <$10.

What exactly are they made of these days, then? :P

LoL.  Almost all cars are still made of steel.  The bodies, the suspension, etc.  Sure most bumpers and facia type items are plastic now.

Anyhow, there is a reason that within the automotive world rust is called cancer however, there is a huge difference between surface rust and deep rust.  With the presence of salt it won't take long for surface rust to progress to something more serious.  The good news is that light rust is easily sanded off and fixed yourself.  If it was me and I wanted to be mustachian I would fix it myself.