All,
I am considering undercoating my Barth. Has anyone used a product they are happy with? I'm guessing I will pressure wash w/degreaser, then Ospho for any rust and then the undercoating.
Any feedback/recommendations appreciated.

I think if I were to do this I would either do the pressure wash, phosphoric acid clean then wash with bicarb and aluminum paint or... have a soda blast then spray the paint. I would not do the asphalt undercoat.
Were I sure there was no exposure of wiring etc. I might opt for sandblasting with paint to follow. Locally there is a company I have used that does semi-trailers. The sandblasting and paint is excellent, quick and gives good protection.

Up here in the land of salted roads and rusty metal about the only thing that works is an oil based rust inhibiting spray that creeps into seams and joints. The two most popular brands in this neck of the woods are Rust Chek and Krown.
Sanding/blasting, priming and painting all rusted parts are followed by a liberal coating of one of these dripless (relatively!) sprays. We repeat the process each year. It takes a lot of cans to do the underside of the Barth and 2 cars. I should find out where to buy the stuff in bulk and get a sprayer with a long extension like comes with weed sprayer.
This stuff is also a great way to lube the levelers and kwikee step.
Don

quote:

The two most popular brands in this neck of the woods are Rust Chek and Krown.

My coach is safe from the salt down here in Texas but lived much of it's former life north of the Mason Dixon and has driven through some salt it appears. I will probably have a semi-shop do as ccctimation mentioned.
Looks like our coaches are very similar.

quote:

Originally posted by Don in Niagara:
Up here in the land of salted roads and rusty metal about the only thing that works is an oil based rust inhibiting spray that creeps into seams and joints.
Don

Interesting. I did not post on this initially, as I thought my information could be old and perhaps out of date.

I have family in the upper midwest who buy LPS3 by the case. It runs in freely and sets up to stay there. Some just use waste oil on their trucks, but I'm sure the heavy metals involved could bring out a toxic spill SWAT team.

quote:

Originally posted by bill h:
Some just use waste oil on their trucks, but I'm sure the heavy metals involved could bring out a toxic spill SWAT team.

Funny... This brought back a visualization... There use to be a saying about Detroit Diesel Engines. It went...

Buy your truck with a Detroit Diesel Dripper and get free undercoating.