GMC Acadia Clutch & Transmission Failure Warning Signs

Had the same auto transmission symptoms on my 2015 GMC Terrain last winter. The torque converter was failing, causing similar lock-up clutch problems and rough shifts. The grinding noise during gear changes turned out to be a serious converter fault that required removing the entire transmission. The lock-up clutch inside the torque converter had worn out completely, causing metal debris to circulate through the transmission fluid. The repair involved: Complete transmission removal, New torque converter installation, Transmission fluid flush, New filter and gaskets, Computer reprogramming Total repair time was 4 days at the shop. This is not a quick fix as the entire transmission needs to come out to replace the converter. The transmission shop confirmed this is a known issue on some GM models when they reach higher mileage. Would recommend getting it checked soon, as continuing to drive with converter clutch problems can cause more extensive transmission damage. The grinding sounds and surge symptoms match exactly what I experienced before the repair.

Thanks for sharing your experience. My GMC had almost identical transmission repair issues, the grinding and erratic shifting were really concerning. The shop also had to pull the whole transmission to fix the lock-up clutch and do a complete overhaul. How much did the automatic transmission repair end up costing you? And has everything been running smoothly since the fix? Just wondering if any other problems showed up later, as I keep hearing mixed feedback about long-term reliability after major transmission work. Would be great to know about the cost to better gauge if what my shop quoted is reasonable. Been a few months since my repair and so far no issues, but always good to hear others experiences.

The transmission repair cost me 2120 Euro for the complete fix, which included replacing the defective torque converter, new seals, and a full fluid flush. This resolved the converter failure and all associated symptoms. After 8 months of driving, the auto transmission is performing flawlessly with no return of the grinding noises or shifting problems. The lock-up clutch engages smoothly now and gear changes are crisp. The transmission repair shop did excellent work addressing the converter fault completely. The investment was worth it since a failing torque converter can lead to much more expensive transmission damage if left unfixed. Regular fluid changes since the repair have shown no metal particles or other signs of wear. The transmission shifts perfectly through all gears with no hesitation or surging. Based on the extensive work needed to fix a defective converter, including complete transmission removal, the repair cost seems to be in the typical range for this type of major transmission work.

Thanks everyone for the feedback. Just wanted to share how my repair went. Finally took it to a transmission specialist who diagnosed the exact same converter fault you mentioned. They had to remove the entire transmission to replace the torque converter and do a complete system flush. The total came to 2350 Euro which included new seals, gaskets, and fluid. Shop had it for 5 days but did great work. The automatic transmission now shifts perfectly, no more grinding or surge issues when the clutch engages. Really glad I got it fixed when I did. The mechanic showed me the old converter and there was significant wear that could have caused major transmission damage if left unfixed. Regular fluid checks since the repair have been clean with no metal particles. Been about 2 months since the work was done. Auto transmission is working like new, smooth gear changes and no warning lights. Definitely worth the investment to have it properly repaired by transmission specialists rather than trying cheaper fixes that might not last.