Rust under trailer on frame parts.

Fluid Film is what I use. It lasts about a year or so then needs to be reapplied. I use it on the tow vehicle as well. Quick and easy, but somewhat messy, so it is best sprayed over a grassy area or put down a cover of some sort. Keep it out of the brakes.

The absolute best stuff is the line of products from POR-15, not cheap though.

Our '85 Wilderness is in pristine shape except for a lot of surface rust on the frame. It was never towed much but we think it was parked near the ocean for many years. I did use a large wire brush to knock off the loose stuff and then sprayed with Rustoleum rust reformer. Worked good under the TT. Didn't work so good on the A frame. I had a hard time removing two layers of old paint that had rusted thru. Hit it with the rust reformer which is also supposed to act as a primer. Rust is coming back thru the new paint, probably didn't get all the rust covered the first time as I have little patience when it comes to painting.

Surface rust does not I affect structural strength in any way that is significant or likely even measurable.

Just clean the area and treat with Rustoleum to improve the aesthetics.

Try Rustoleum Rust Reformer

My trailer had quite a bit of rust on the frame so I used Rust Kutter on it and then painted it with Rustolium paint that I brushed on.

The Rust Kutter will neutralize the rust and you can then paint right over it. No need to rinse it off. If you spray it on, you need to wear a respirator as the fumes are quite bad. I put it on with a brush and painted the same way. Still looks great 4 years later.:)
Barney

Rattle can spray on bed liner works well too. Stands up a little better than paint...

westend wrote:
You probably don't have a lot of rust at three yrs. old and living in Ontario, unless you fly South each Winter and park on a beach.
...

Saw a brand new trailer with lots of corrosion, not just on the frame but on the metal propane plumbing and tanks, metal steps, and elsewhere. A $30K trailer that had been hauled all the way from the Oregon factory some time in the winter over salted roads. You could still see the road salt on the frame ledges as the dealer hadn't taken the time to wash it down. Yuck.

You probably don't have a lot of rust at three yrs. old and living in Ontario, unless you fly South each Winter and park on a beach.

I use water softener cleaner (liquid), diluted two parts water/one part cleaner for mild surface rust. The phosphoric acid will neutralize the rust. Rinse off after a day and topcoat with your choice of oil based paint.

Our Springdale TT came to us with a considerable amount of rust on the frame and joints and such. One of first things I did was to "try" to brush and repaint. Well, the brushing became a real pain in the neck real fast, laying on my back on the ground ... didn't I give up laying on the ground when I gave up tent camping?... anyway, I finally just went right for the paint. I used black Rustolium metal "oil based" rust inhibitor spray paint (about 10 cans of the stuff) .. wasn't cheap .. getting that much at once ... and took to spraying everything I could see under the trailer. Worked great!

Next year I crawled completely under the trailer again and inspected (early spring) like I always do. I then bought about 3 cans of the stuff and sprayed the spots I obviously missed the year before.

Well, 6 years later (3 weeks ago) we traded for our new Outback. Before trading, I DID crawl under the trailer, and poked around with a poker, did a little scraping here and there, and had another spray can handy. Except for the areas where I poked, after 6 years, no rust, and the paint was still holding fast. There were a few places where rocks and such had hit on the frame, you could tell by the chips, but no apparent rust. What little was there was just surface. So the Rustolium held pretty good, and the underside of the trailer STILL looked real good!

Rustolium (the oil based version) has a rust inhibitor that actually penetrates and stops rust. You don't need anything else. Shop wisely, and don't be afraid to spend an extra dollar a can. Considering your camper probably cost over $20,000, 5 extra dollars to give your camper 6-8 years of trouble free service is well worth it!