Can you share some of your issues?
Buffeting vibrating issues for the 1st year. After multiple sets of tires, I went to an independent tire shop an purchased a set of michelins and made sure they all road forced under 15lbs. Shop ordered 8 tires just to be safe as they knew what I had been dealing with. They improved the buffeting for the most part although it can be felt at times and more often now being that the tires are 50% worn. This was all out of pocket as GM was not willing do anything other than re-balance oem tires and a couple other TSB that had been issued for the buffeting problem. An Engineer working on my case told me they weren't having much luck with the TSBs for the buffeting so I elected not to have any of them completed...driveline related, reseal roof bows, etc.
-Buffeting - Even though the tires masked most of it, I still get complaints from some after riding in truck for long periods.
-Low speed booming when going over any imperfection (supposedly dampers can be installed to correct this problem on 15/16 models)
-Steering column bearing spring defective (common with 15s and maybe early 16s)
-Main oil line leak (replaced under warranty)
-Tranny leak in two places (not covered under pwr train)
-Rear ring and pinion replaced at 35k and is need of work again (55k miles)
-Front Ring and pinion is making noise but have not yet had it replaced
-Adjustable brake/gas pedals stopped working...fortunately they are frozen in an okay position
-Dealer claims both front and lower control arms are worn out and need replaced ($2k repair.) Dealer also claims that this is common (wtf??) we are not replacing.
There are other small items that are somewhat typical of any vehicle but the above are the main items over the past 20mos that are unacceptable not to mention how GM has handled most of it. However, the buffeting is the killer...I know there are lemons and we were ready to trade for a 16 or 17, but I've been in countless trucks and majority have the buffeting issue so each time we passed on the idea.
My best advice is to drive the truck for a few days and go from there. It's very clear that many don't feel the buffeting problem and are very happy. Also, if buying used, try to really dig for the history as there are a ton of low mile trucks on the used market (wonder why???)
Good luck!
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