Underbody Rust - '96 Grand Prix

[quakerj]

I have a '96 Grand Prix I'm fixing up and underneath the car there's a substantial amount of rust underneath the car in places..  We typically don't get rust real bad here (northern KY) but after 24 years on the road, it's starting to show.

Anyone here have any experience repairing rust underneath the car?  I've seen some at the junkyard that are downright scary (one had the trailing arm mounts literally rip right off), mine is nowhere near that bad.  But it needs some attention before it gets worse.

[Amanita]

Mine is fairly rust free but there are a few spots that have shown some issue. To take care of rust what I do is I scrape away as much of it as I can with a wire brush and then seal it over. Pretty standard procedure, I've only used Rustoleum but I imagine there is something that's much more durable to use on the underside of the car. Check under the battery, that was the spot with the most rust on my car but since it was a southern car most of its life its pretty good otherwise.

[digitaloutsider]

Do you have any pictures of the rust?

[runt]

I agree with digitaloutsider.  We need to see pictures.  If you were in PA asking about rust...I'd likely tell you to scrap the car.  My hope (and assumption) is it's only surface rust with minimal penetration into the structure. 

[rockfangd]

I would say you are lucky. Most where I live rotted out over 10 years ago.

My Cutlass Supreme trailing arm mounts rotted right off. 

I would scrape scale, then coat it well. If you do not scrape first it will continue to hold moisture and rust.

I like Chassis Saver. But it runs $100 per gallon. Good stuff though