AMG GT Gearbox Issue Resolved

Gear grinding and unclean shifts definitely point to potential issues within the transfer case. A transfer case is responsible for distributing power from the transmission to both the front and rear axles in all-wheel-drive vehicles. I have the same model and had similar symptoms a while back. Check the transfer case oil. If it's low or looks burnt, that’s a red flag. If the gear wear is significant, that can cause the problems you're describing.

Burnt oil is a good call, I'll check that out. When you had the issue, did you notice any visible oil leakage? And how bad was the gear wear when you took it in?

I didn't notice any obvious oil leakage myself, but the workshop confirmed some seepage around the transfer case seals. The gear wear wasn't catastrophic, but enough to cause the shifting problems. Honestly, I'd suggest getting it professionally diagnosed. Better to catch it early before it leads to more significant damage. Get the transfer case properly inspected.

Thanks. Took it to the workshop. Turns out it was the transfer case. Gears inside were indeed showing wear. They replaced the oil and some worn components. Bill came to 330€. Shifts are smooth again. Appreciate the advice!