Undercoating flaking off lets talk replacments

[srgtlord]

So my newly aquired 85 golf is beautiful and rust free but the undercoiaing is flaking off almost like paint chips in various areas. What product would you guys recommend for undercoating?

[audilvr]

fluid film. soaks right into the metal.

[srgtlord]

I was looking for something close to the factory undercoating

[bbob203]

I would reapply undercoating and get it oil sprayed.

[smutts]

The hard undercoating is great until it starts to fail, then it actually holds damp against the metal, causing creeping death of rust unseen till it is too late. After I pushed my finger through the rear chassis in a few places I found lots of welding needed. Glum.

[the caveman]

On my last car, which I intend will last  through the next 10 Montreal winters, I started by cleaning the underneath with a very strong cleaner, followed by pressure wash. Then I bought the OEM VW  grey urethane coating product, which comes in a tall can and needs a special spray unit, but available at good parts stores. BTW the next thing I did was to remove the seats and carpet and removed the felt underpadding and replaced it with closed cell rubber padding, sprayed rust preventative before reinstalling the interior. Of course I sprayed preventative undercoating in and under the whole car. Not a spot of rust so far after 2 winters

[hillfolk'r]

Here's a good substitute for the beeswax. It's light, probably would need 4-5 coats to look factory. But I took a piece of bare steel and sprayed it 2 years ago and left it outside. There's like one little pinhead sized rust spot.

[mystery3]

I'd use this stuff: http://www.semproducts.com/product-catalog/rust-and-corrosion/undercoatings/

SEM products are great.

[fatmobile]

 I use the SP 400 too.
 I think LPS3 is about the same thing.

[theman53]

If you want permanent rust coating there is nothing better than Rust Bullet. It is expensive but it works. Better than LPS3, por15, and extend or anything else I have used in Ohio salt. It says on the can that if you use 2 thin coats you can use it in the ocean salt water with no fear of rust. I haven't done that but I believe it with what I have seen.

[srgtlord]

I actually had some time to work on the car yesterday and settled upon 3M professional undercoating. The directions say to apply 2 coats for best results. We will see how long it lasts. IF/ when this stuff flakes off I am going with rust bullet.

[theman53]

Rust bullet works on the bare metal and is a thin coating. You could use an undercoating afterwards but not needed. 3M Rocker Shultz I think is how it is spelled is a good undercoating product too.

[Dakotakid]

He's not kidding about the Rust bullet. You can slather it on rusty, thin metal and it hardens like new metal. Amazing stuff....probably better wear really good eye protection when applying it.

[8v-of-fury]

I must get some of this..

is it like a converter/epoxy coating?

[theman53]

I get mine at summit racing. It is expensive, but the only thing I have found worth every penny of rust protection.