What do you guys like to use for undercoating? Any brand that I should stay away from?

Anything you really like and why? (Spray can stuff)

Thanks!

 

Ive been using zinc cold galvanizing paint for inside panels and stuff. I coated the rockers with the stuff when I replaced them a couple months ago.
I did have a spot on the outside show some rust afterwards, but I think its because I didnt put the paint on thick enough or shake the can enough.
As for the frame, eastwood has some ceramic frame paint I might try.. but for the moment black epoxy primer is my fav.

 

It kind of depends on how much effort you want to put in. If you don't want to take the bed and cab off and wirewheel everything, then you are stuck with some less than optimal methods like the redneck one where you paint the underside of the truck with used heavy oil and go drive around on dirt roads. If you are willing to do the prep-work, cold tar epoxy is wonderful stuff. Personally, I decided that putting that much work in is not worth it since although there is a lot of surface rust, there is no real structural rust and I don't think there will be before I wear the truck out.

 

I had my box off for my short box conversion so I bought a wet sand blasting kit (power washer nozzle with an eductor to suck sand into the stream) and then painted with rustoleum. May not be the best but way cheaper than the alternative anti rust coatings, and way easier that laying under the truck with a grinder.

 

line-x and do it right