How to Prevent Rocker and Cab Corner Rust

[zmaddox5306]

I just picked up a 2004 GMC Serria regualr cab long bed 4x4. It is rust free (except the rear bumper, which I plan on replacing) and the paint is in impecable shape. Now my question is what can I do to help prevent the rockers and cab corners from rusting like so many of these trucks do?

[RyanbabZ71]

keep up on cleaning it and seal/wax the truck regularly (2x a yr)

[KMGZ400]

Like said above.. Hose or pressure wash it out good weekly if your in the salt belt

[waumo1]

What I did on my 1998 (different body style I know) is rustproofed the rockers, wheel arches, etc with Rusfre innerpanel rustproofing, It was still perfect when I sold it 2 years ago and it spent most of its life outside. If you already have a compressor, the gun used for the rustproofing is not very expensive. The trick is to gain access to the back or inside of the panels. My 1998's rear bumper disentigrated (literally) and I replaced it. I noticed the rear bumper of my 2011 is coated with something which will hopefully prevent the problem.

[brucelimerick]

My 2001 rockers went 10 years and one month. 10 year warranty. What caused them to go was the stone chips from the front tires on gravel roads. I live in Ontario and winter salt is heavy. One other thing I have noticed is my frame is in poor shape. The coating GM used on it peeled. I have noticed on a few of my ex's foreign cars that undercoating does work. Krown is the only CAA approved coating here in Canada and I'm trying it on my new Accent. I'm also trying 3M's stone guard, a tough clear plastic that is put on buy the auto detailers. I have had the rockers done between the wheels. It is supposed to protect the paint from stone chips. The body on my Sierra is good except for the rockers. The stones chipping the paint and then the primer exposing bare metal to the salt is a killer. My non treated wheel wells are fine as well. Ditto on the back bumper. But the frame bracket holding the bumper on is not in good shape, A body is no good unless the under pinnings are good. I'm hoping the rust proofing will protect the frame and other areas not exposed to stones. It is also protecting from corrosion from the inside out. I think anything you can do to protect the underbody is a good idea from my experience.

[2017SierraSLT]

On the GMT900 extended cab bodystyle, the cab corners are easily cleaned and treated. They are accessed through the hinge opening in the door jamb. I sprayed mine with Fluid Film and flush regularly.