SQ5 Torque Converter Issues: Warning Signs & Fixes

Had almost the exact same issue with my 2015 S4. Based on my experience working on various cars, these symptoms strongly indicate torque converter problems in the automatic gearbox. The transmission warning lights and gear slipping were identical to what you describe. The auto transmission began showing issues during gear changes, especially between 2nd and 3rd gear. After initial diagnosis, the workshop confirmed a faulty torque converter that was causing the transmission fluid pressure to fluctuate. The repair involved: Removing the transmission, Replacing the torque converter, Installing new transmission fluid, Resetting transmission control modules, Test driving to verify proper shifting Total cost was 2120 Euro including parts and labor. The repair resolved all symptoms and the transmission has worked flawlessly since. To provide more specific guidance, could you share: Current mileage on your SQ5, When the symptoms first appeared, Whether the engine surge occurs at specific speeds, If the transmission fluid has been serviced recently, Complete error codes from the diagnostic scan This information would help determine if your situation matches what I encountered and whether similar repairs might be needed.

Last service was at 75000 KM with new transmission fluid. The engine surge started appearing about 2000 KM ago, particularly noticeable during moderate acceleration. Diagnostic scan shows P0741 torque converter clutch circuit performance code and P2797. These symptoms are quite concerning given the relatively low mileage at 80532 KM. Compared to the described repair scope, hoping my automatic gearbox issues might be resolved with just a converter replacement rather than a complete transmission rebuild. The clutch problem seems similar though, especially with the grinding noise during shifts.

Thanks for the additional details. Those error codes match exactly what I encountered with my S4 when the torque converter started failing. The P0741 specifically points to lock-up clutch issues, which aligns with the transmission symptoms you're experiencing. The good news is my repair only required replacing the torque converter, not a full transmission rebuild. Given your mileage and the fact you had recent transmission service, the scope should be similar to my case. The engine surge during acceleration is a classic symptom of converter failure, I noticed the same behavior before getting mine fixed. The grinding during shifts occurs when the lock-up clutch starts slipping and cant maintain proper fluid pressure. With the repair cost breakdown from my case: Torque converter: 890 Euro, Labor (8 hours): 960 Euro, Fluid and miscellaneous: 270 Euro One tip: make sure they check the transmission cooler lines while the units apart. My mechanic found minor wear there which we addressed during the converter replacement. The repair completely resolved the transmission warning lights and restored proper shifting performance. Four years later, no recurrence of any converter fault or clutch-related issues.

Thank you for sharing those repair costs and details about your S4 experience. The very similar error codes certainly help confirm my converter fault suspicion. Scheduling a repair next week based on your feedback, as waiting could risk additional transmission damage. Based on your timeline, good to hear that replacing just the torque converter resolved the auto transmission problems. Having transmission service history with fresh fluid should help minimize the repair scope needed. The total repair estimate I received of 2350 Euro seems reasonable compared to your costs, considering recent parts inflation. The grinding noise and converter lock-up clutch symptoms match perfectly with what you described. Will make sure they inspect those cooler lines during the repair, smart suggestion given they'll have clear access. Hope to have similarly positive long-term results once the transmission work is complete. Will post an update after the repair to share the final scope and confirm if it fully resolved the gear slipping and warning lights. Really helpful to compare notes with someone who went through nearly identical converter failure issues.