Not necessarily a better idea but coating the frame with POR15 is probably overkill. How much actual work , mud, grime salt, water, etc is your truck going to see when you're finished? Probably none.
I used 12 rattle cans of Rust-O-Leum semi-gloss black to paint the entire undercarriage of my 1956 Cadillac. I did this over 15 years ago.
I use my car as a daily driver but it doesn't see road salt or anything like that. The Rust-O-Leum still looks like brand new under there. I sprayed it directly onto cleaned metal with no primer.
Your frame is entirely exposed and easy to get to. Clean it as best you can and go straight to the Rust-O-leum. Use a Rust Converter first if you wish.
Last edited by Otto Skorzeny; 10/21/2022 4:40 PM.
