Floor pan rust is one of the most common issues on 1947–1972 C10 trucks. Here’s a step-by-step overview of doing it right.
Step 1 – Assess and Order the Right Panels
Floor pans come in full replacement (driver, passenger, full cab) and partial sections. For most trucks with typical floor rust, the driver side full floor replacement is needed. Measure your floor and order the correct year and side.
Step 2 – Remove Interior
Pull the seat, seat tracks, carpet, and insulation. Map out all the rust from above and below before cutting.
Step 3 – Cut Out the Old Floor
Use a cut-off wheel to cut the rusted section with 1–2" margin into solid metal. Mark your factory spot welds with a marker and use a spot weld cutter to separate them cleanly.
Step 4 – Prep and Treat the Frame
Before the new floor goes in, treat the frame and body rails with Rust-Oleum 2-in-1 Rust Reformer and let it fully cure.
Step 5 – Fit and Tack-Weld the New Pan
Fit the replacement pan, clamp it in position, and tack-weld it in place. Check panel gaps to the firewall and door sills before running full beads.
Step 6 – Protect Before Closing Up
Apply 3M Weld-Thru Coating to all lap joint areas before final welding to prevent rust between overlapping layers.
Step 7 – Final Welds, Grind, and Coat
Full weld the seams, grind smooth, then apply seam sealer to all joints. Spray undercoating from below and add insulation above.
Questions about your specific year? Drop them below.