The 2014–2018 K2XX Silverado/Sierra can develop cab corner rust, particularly in salt-belt regions. Here’s how to catch it early and what to do about it.
Why K2XX Cab Corners Rust:
The lower cab corner seam – where the outer skin meets the rocker panel and cab structure – traps road debris and moisture. Combined with paint chips from road debris, rust can start at the seam and work inward.
Early Detection Signs:
- Paint bubbling at the very bottom of the cab corner (below the door)
- Tiny rust dots appearing along the lower seam
- Brown or orange staining appearing through the paint
How to Inspect:
- Run your hand along the lower cab corner seam
- Look for soft spots or paint separation
- Check inside the door jamb at the lower corner
- Inspect inside the wheel well at the front and rear cab corners
Stage 1 Treatment (Surface Only):
If caught early (no perforation):
- Clean the area with rust-removing cleaner
- Sand to bare metal
- Apply Rust-Oleum 2-in-1 Rust Converter
- Prime and paint
Stage 2 Treatment (Light Perforation):
Requires patch panel welding or panel adhesive repair – best done by a body shop.
Prevention:
Apply underbody spray or coating to the lower cab corners and rocker areas annually. Pay special attention before winter.
K2XX vs Older Trucks:
The K2XX is a newer platform, so rust is typically caught at earlier stages than GMT800 or GMT400 trucks. This makes the repairs much more manageable.
What rust have you found on your K2XX? Share your mileage and climate!