Prevent Rust on Solid Body Parts

[letitsnow]

I do mine once per year, in the fall.

 

[CumminsBronco]

Northstar, I have yet to do it. I bought my Sub out if Az and have just now got it on the road. Took me a yr to get it to this point, did a Cummins swap along with 1 ton SAS.
From my research if the product, it was developed by a guy in the Northeast and was used by highway depts. to protect their snow removal equipment, giving it a spray coating each yr.
How often to use it might be open to what conditions your truck us subjected to....I don't know, but seems like pretty cheap insurance to me. I think letitsnow has the right idea with an annual application.
I've given the underbody of mine a good covering with KBS Diamond Coat clear coat and will use the Fluid Film inside the rockers, rear quarters, and other areas that are "enclosed".

 

[herkyhawki]

Also look at "3M Cavity Wax", and Cavity wax applicator wands. The wands up to 3 ft long let you drag it through the rocker while spraying.

 

[NorthState]

sounds great, @CumminsBronco, @letitsnow and @herkyhawki in going to see about getting some!