SQ7 Trans Grinding: Lock-Up Clutch Failure Alert

As someone with moderate repair experience, I dealt with a very similar transmission repair issue on my 2017 Q7 diesel last year. The symptoms you describe match almost exactly what I experienced, rough shifting, grinding noise and transmission warning lights. Initially thought it was a minor transmission control issue, but diagnostic testing revealed a severe converter fault. The torque converter showed signs of internal wear, affecting the lock-up clutch operation. After consulting multiple workshops, I learned that this particular transmission issue often requires replacing the entire converter assembly. The complete repair included: New torque converter, Transmission fluid change, Software update, Comprehensive testing Total cost was 2120 Euro including parts and labor. The repair took 3 days to complete, but solved all transmission-related problems. No issues since then with shifting or warning lights. Before suggesting specific solutions, could you share: Current mileage, Service history details, Full transmission fault codes, Type of transmission fluid used in last service, Any previous transmission repairs This would help determine if your converter failure symptoms match what I experienced and whether a similar repair approach would be suitable.

My current mileage is 115565 KM and the last service was performed 2 months ago. The automatic gearbox was displaying similar symptoms initially, but after clearing the fault codes and cleaning the transmission valve body, the engine surge and transmission warning lights continued. The lock-up clutch problems persist even after replacing the transmission fluid. The torque converter issue you described closely matches my experience. Based on the repair details you shared and the 2120 Euro cost breakdown, this seems like a reasonable solution. Would you happen to know if the new converter assembly comes with an extended warranty?

Thanks for the additional details. The symptoms you describe, especially the persistent engine surge and warning lights after the valve body cleaning, strongly indicate a torque converter issue rather than just a control problem. The new converter assembly I had installed came with a 24-month warranty on parts and labor. The warranty covered any potential converter failure or lock-up clutch malfunction during that period. Given your mileage and the failed attempts at simpler fixes, I recommend proceeding with the complete torque converter replacement. The continuing transmission problems despite the fluid change typically points to mechanical wear inside the converter, exactly what I experienced. A quick note about post-repair expectations: after my converter replacement, it took about 500km for the transmission to fully adapt and achieve optimal shift quality. The automatic transmission needed this adaptation period to properly calibrate the new lock-up clutch timing. Word of caution, during my repair process, I learned that using non-approved transmission fluid can accelerate converter failure. Make sure your workshop uses the exact specified fluid type for our transmission model.

Thanks for that detailed feedback. I think I'll move forward with the torque converter replacement since all signs point to this being the core issue. Your experience with a similar automatic transmission problem has been really helpful, especially knowing about the adaptation period after the repair. I just contacted a transmission repair specialist and they quoted 2350 Euro for the complete job, which seems reasonable given your cost reference. Good to know about the 24-month warranty coverage for the lock-up clutch and other converter components. Will make sure to specifically request OEM-spec transmission fluid and get written confirmation of the warranty terms before proceeding. Really hoping this fixes the engine surge and shifting issues like it did in your case. Will book it in next week and just manage the rough shifting until then. Thanks again for sharing your repair experience, it helped confirm my suspicions about the converter being the root cause.