My 98 Pontiac Grand Prix GTP is leaving parallel (front-to-back where the tires are) yellow-orangish stains in my driveway. I can't find any leaks.

There is no rust on the outside but last fall when I took it in my mechanic said it was rusty underneath. I will call him and see if anything can be done but I do not want to put much money in a 20 yr. old car. There is no rust on the outside but last fall when I took it in my mechanic said it was rusty underneath. I will call him and see if anything can be done but I do not want to put much money in a 20 yr. old car.

Have the vehicle oil sprayed with an vegetable oil based rust protection (Rust Check,Krown, etc) and make sure they also inject it into the rockers,that will slow the rust.DO NOT use a hard coating type product for rust protection. Have the vehicle oil sprayed with an vegetable oil based rust protection (Rust Check,Krown, etc) and make sure they also inject it into the rockers,that will slow the rust.DO NOT use a hard coating type product for rust protection.