scottym74

My 2015 Sierra Denali 6.2 8 speed was dropped off at the dealer yesterday with the same vibration. Thud occurs normally when rolling up to a stoplight and stepping back on the gas. Vibration occurs when accelerating with a light foot as the engine revs through 1500 to 1600 rpm. Also, at any stready speed that has the engine at that rpm. 47 mph, 58 mph and 67 mph. Almost like the transmission is slipping or the computer cannot pick what gear its wants to be in. Service writer wrote it up yesterday afternoon. This morning after a short test drive and 5 minutes of research the dealership calls me to tell me it is a issue with the torque converter. A known issue. A new and improved torque converter will be available soon or I can request a new transmission with the new torque converter and latest software/firmware control updates. I requested a new transmission because who knows what this junk one has done to the trans. All of this is supposedly documented in a Technical Service Bulletin that came out last month- mid-October 2015. I did not get a bulletin # and could not find anything on line about but I am driving a dealer loaner for the next week or so while they get the new transmission in. I did not have to speak to anyone other than the service writer. Hopefully my truck comes back fixed and these issues go away. Already had the ujoints on the driveshaft fixed a few months back.