Not sure if this is the right place to ask questions, but I thought I would try. 

I bought a 2008 Sierra All Terrain 12 years ago, wow time flies !     

Totally love the truck and thought I took really good care of it. 

Now however, I've got rust developing on each side of the rear fenders. I see many trucks of this same age with the same problem.

Does anyone have any experience or comments on how to fix this so I can keep the truck looking as good as possible as long as possible?

I see a product called "rust converter". Im thinking of sanding off as much rust as I can, then applying rust converter. Sanding is smooth, then painting with a rust inhibiting primer. Then attaching some bushwacker fender flares. 

Any advice?

 

 

 

That's pretty much your only option, apart from cutting/welding.
My '04 is rusting there, tho it has factory flares and the rust hasn't come out from behind them yet.
I don't mind really, as it has 197,000 miles on it.

Honestly, I would not go with your stated plan, unless you plan on trading/selling the truck immediately afterward.

The longest lasting repair involves cutting out and replacing the affected panels, either whole with OEM parts, or with aftermarket "patch panels" that would span the area known to rust (cut out the area above the wheelwell and weld in the replacement partial panel).  Just treating the outside surface of the affected panel is a waste of time, as by the time you see the bubbles outside, the inside is already gone, the problem starts inside and will quickly visibly return unless the whole affected area is replaced.

Wheel flares actually exacerbate the problem because they hold moisture.  The panel needs to "breathe" so moisture dries inside the panel.  Wheel flares prevent air circulation.  Here in PA, I cannot tell you how many times we've gotten a pickup truck (mostly Dodges with factory flares, but also GM '07-'13 with aftermarket flares) in the shop with bedside damage, a wheel flare takes a chunk of rusty bedside panel with it when it is removed, totally complicating a collision repair.  The rocker panels and cab corners rust out on Fords of the same era.

The '07-'13 GM trucks were engineered during lean times at the corporation.  I am not sure if it was a metal quality problem, or a lack of designed-in drainage function to prevent the build-up of dirt/moisture inside the bed panels, but the problem is way too common (with or without aftermarket wheel flares) at least here in my area of the country.

That is a beautiful truck, sorry you have to deal with this.  It's too soon, imo!

Edited February 16, 20205 yr by ocnblu

Thanks so much for the replies. I think it might be time to trade up to another truck. Talked to a repair shop about cutting and replacing a panel, and that would cost me more than i'd probably be able to sell the truck for. Even then, they said rust will likely show up in other areas before long. Loved the truck and thought I took pretty good care of it. Maybe a little more attention to cleaning behind the wheel wells would have helped. 

Thanks again!