i used waterproof expanding foam to fill my frame, then prof. rubberized undercoat for external coverage. works great for me, but we don't have salt licks, stacked up on the roadside, for winter precipitation.

 

if your frame is filled with expanding foam, where do you put all illegals at boarder crossing.

 

In jerry cans on his roof.

 

I treated two cars in the UK with Waxoyl when they were about 8 years old, a Ford Cortina and a Citroen CX. Both notorious rustbuckets. They were both kept another 5 years, and we saw no new rust on either vehicle. You have to be diligent about getting it into every cavity. You will probably have to drill a few holes. I had a supply of rubber plugs for the holes I drilled. I'd consider it ideal for injecting into the chassis. It works well anywhere it isn't directly exposed to spray.

You need to pick a really hot day, as the Waxoyl flows best when warm. Must have used about 3 1-gallon cans for the CX. I injected it inside any box sections, sills, inside doors (make sure you don't plug the drains), hood and trunk box sections, inside the fenders, chassis rails. The rear of the front fenders and the box section hehind it under the A pillar are common rust traps.

 

i thought we established, that was the reason for dumping sls........big frame mounted black box.

 

It's similar to POR15. The problem is that the frames rust from the inside out in most cases. The first thing I saw was swelling along the top and bottom welds on the frame, typically at the rear rails. In order to effectively stop the corrosion you have to get inside the box frame. That's where waxoyl works at it's best.

 

^^that was my thought with the waterproof expanding foam filler. dunno if it helps or hurts but no more moisture in there.

 

are you sure the foam does not adsorb moisture? Is it closed cell? I've heard many horror stories of boats where water has got into polyurethane foam that was used to fill the voids between hull sections, and the resulting mess is horrendous.

 

That's what I'd be afraid of. The beauty of the boxed frame is that it has exit points for water and debris.

 

I am going to use this for the inside of the frame.

Eastwood Internal Frame Coating