do products like Ziebart or Rust Chek serve ANY useful function in extending the life of the cars body/frame? In areas of the country where sand and salt are spread in winter..does undercoating the vehicle help, or is it a pointless waste of money??

 

I suspect that in areas where a lot of salt is used, it would provide and extra layer of protection for the car. I think, however, that cars these days are all very well prep'd for the salt and such. And unless you have exposed metal surface, I don't think you should have much problem with rust.

-Shing

 

Any car has some weak points. The best way I think is to locate these spots (for example, through discussing the problem on the forum) and to focus your anti-rust activity on them. This is undoubtlessly useful.
Usually the other parts of the body, etc. last forever and to "overprotect" them with expensive chemical agents seems to waste money and time.
Also try to find any NisSTB on the problem.

Regards,
DDD

 

I know one problem with undercoating was that if it cracked or had a hole, the salt would collect there and cause more rust. Is that only the older process, or does that still apply now?

 

there is no benefit in an aftermarket treatment - all cars are adequately protected from the factory.