Four problems related to equipment have been reported for the 2011 GMC Sierra. The most recently reported issues are listed below.
On July 29, 2015, while driving at approximately 45 mph, the vehicle suddenly downshifted itself into first gear causing the vehicle to slow down suddenly with no notice. I was able to get the vehicle off the road and into a gas station. After the fact the check engine light was illuminated. The vehicle was towed to the dealership. I was told the tcm (transmission control module) needed replacing and that there is a known issue with this year truck. This is a very dangerous situation to have your vehicle suddenly slow down while driving at speed. If gm knows that the part is faulty why is there not a recall? will it take multiple deaths before gm takes responsibility?.
In very cold weather, the shifter sticks and will not move to shift in any gear.
The front bumpers plastic fog light assembly becomes lose and falls off. This can cause crash and accident because of falling off parts from car. This seems to be a known issue with the plastic bumper parts for the fog lights. The suggestion is to replace this with a chrome or metal bumper so that plastic peaces do not become warped and break off. This happens at the bolt points for the front bumper fog light holder entire plastic peace.
Three out of four tires had separation. The tires are goodyear wranglerlt265/ 60r20e1. Two tires were replaced on 2/21/2014 due to separation of left rear tire. We chose to replace both rear tires. On a recent vacation to florida from texas, the front left tire, same goodyear type tire, separated. Our spare replaced the front left tire. On the return trip from florida back to texas (same vacation), the front right tire began separating when we were on the east side of louisiana. We were unable to locate an open tire store, as it was a Sunday. So, we drove home slowly the remainder of the trip. After returning home, discount tires (where we purchased the two new rear tires in Feb. 2014) ordered us two new front tires. The tires were shipped from chicago, due to the unusual size of the tire (we were told). Is the goodyear wrangler tire a safety hazard, since three out of the four tires failed? was it the 'lot' that was bad? we were told by discount tires that there wasn't a recall on this tire.