berty

When it comes to boats, I know Boeshield T9 is what everybody suggests. Do you think that has a place on the car? You think maybe treat the metals with T9 first to clean and then Rustoleum after it dries to protect and make it look good?

chickenwire

lol - isn't THAT the truth? Have a Pontiac Solstice that needed a catalytic converter replacement a few years ago. Couldn't seem to get a replacement and I honestly believe it was because the supplier was left with a ton of unpaid bills when GM went bankrupt. Another owner in CA was informed through a forum about this shortage and his dealer told him "You can't believe anything you read on the internet."

I told him "Does he believe all of us who are waiting for a catalytic converter are just sitting in our basements, making this !@$ up?" lol

Captain Bob

speaking of rust.... is it worth having the underneath undercoated on a new truck nowadays? My last truck was not undercoated and it held up pretty good. My 97 F150 on the other hand, lasted 14 years before it turned to crap underneath. Neither truck was undercoated. Thoughts?

Taggart

The steel and paints they use now area a lot more rust-resistant than they used to be. That was the big thing when I was a kid up north - the roads were salted all winter, and cars were made with non-galvanized steel. You always got the undercoating, but that still didn't prevent everyone's rocker panels from rusting through in about 5 or 6 years. Now they don't seem to rust much anywhere.

Blown F-150

I've seen cases where undercoating has caused more issues than leaving it alone. If the coating isn't applied really well or not on a brand new vehicle, you can get corrosion between the coating and the metal surface. This allows it to "fester" and collect moisture. If you run on any gravel, I recommend staying away from something like the rubberized undercoating and just treating it with something more like POR-15, it adheres better and contains high amounts of Zinc. You can also find "Zinc Rich" Rustoleum spray paint at Home Depot. With the Zinc content, it helps even if rust is already present. Sprays like Fluid Film also work really well, but need to be re-applied yearly.

broderp

Well put, however, rust requires oxygen to do it's thing. In theory, if you have rust and you trap it, as in truly seal it up so no more oxygen gets into it, then it should not get any worse. It's only if it's not sealed that the moisture and air can interact with the metal and rust out from the inside.

Even with self healing methods or sprays, a good enough rock or chip can compromise the barrier and allow some rust.

I'm not familiar with spray on oil like protection, this is actually the first time I've heard of it, but it seems like the best method, even tough it must be reapplied every year. The cost is also much less than that of traditional rust proofing.

Blown F-150

Agreed 100%, but it is very unlikely to do a really good job of cutting off all oxygen. It always seems to find a way!

Snowdog

20 or so years ago there used to be a product sold at tractor dealerships that you would paint over rust with a brush that would stop the oxidation and stiffen up the already rusted parts. i used it on an old Cavalier I ran as a winter beater and it worked well. I can't remember what it was called. That may be worth looking into.

Martian

Rust encapsulator. Eastwood makes a good one, but be prepared to spend for it. It's on Amazon.

Captain Bob

Wasn't there also a product called "XO"? May have been by Krylon. I used it in the past but can no longer find it. It seemed to work pretty well. Just paint it on after removing loose rust and you are good to go. The stuff would turn black after it was on the metal for a few minutes.