SQ8 Transmission Troubles: Rough Shifting & Grinding

Having some experience with Audi transmissions, I encountered a similar issue with my Q7 (2019) diesel. The symptoms matched yours, rough shifting and grinding noises, particularly noticeable during gear changes. The transfer case oil leakage was the initial concern, but inspection revealed defective gears in the transfer case causing mechanical wear. The repair involved complete disassembly of the transfer case, replacement of worn components, and fresh transfer fluid. Total repair time was about 4 days and cost 330 Euro including parts and labor. Before committing to such repairs, helpful details would be: Current mileage, Service history, especially transfer case oil changes, Any warning lights on dashboard, Whether the grinding occurs at specific speeds, If you notice any unusual vibrations or fluid leaks These symptoms often indicate progressive mechanical wear in the transfer case system, which typically worsens if not addressed promptly. Regular transfer fluid checks and changes can prevent such issues, but once gear damage occurs, replacement is usually necessary.

Thanks for the detailed response. My current mileage is 177871 KM, and the last major service was the 160000 KM interval. No warning lights showing, but I notice the gear grinding primarily between 60-80 speed with medium acceleration. Started seeing small drops of gear oil underneath after longer drives, suggesting potential transfer fluid leakage. Vibrations are minimal but noticeable during gear changes. Planning to book a service visit soon since the gear wear seems to be getting worse each week.

Thanks for providing those details, they really help narrow down the issue. Given those symptoms, especially the oil leakage and worsening gear grinding at specific speeds, this matches exactly what I experienced with my Q7 before the repair. The oil spots you notice are particularly concerning as they indicate active transfer case oil leakage, which can accelerate gear wear dramatically. In my case, waiting too long after spotting the first leaks led to more extensive gear damage. Since your vehicle recently passed the 160000 KM service, but the symptoms persist, it points strongly toward mechanical wear rather than just maintenance issues. The progressive worsening you describe mirrors my experience exactly, what started as occasional gear grinding quickly developed into consistent shifting problems. A full transfer case inspection is definitely warranted. Based on repair costs today, you should budget around 400 Euro-500 Euro if gear replacement is needed. The good news is catching it now, before complete failure, could prevent more expensive transmission damage. Quick tip from my experience: while waiting for the service appointment, try to minimize aggressive acceleration and high-load situations where possible, as these can worsen gear wear when there is an active oil leakage situation.

Thanks for all this helpful information. The gear oil leak situation definitely seems similar to what you experienced. Looking at the repair costs you mentioned, I will need to budget around 500 Euro, which is actually less than I feared. Glad to hear catching it early might prevent bigger transmission problems. I have already scheduled a workshop appointment for next week. Until then, I will follow your advice about gentle acceleration to minimize further gear wear. The transfer fluid leak and gear grinding are concerning enough that I dont want to risk making things worse. Will probably have them do a complete transfer case inspection and gear oil change while they are at it, given the mileage. Better to address everything at once rather than face more mechanical wear issues down the road. Really appreciate the guidance on this. Its reassuring to know others have dealt with similar transfer case problems and got them resolved successfully.