Mercedes SLC diesel gearbox issue

A slipping gearbox on your Mercedes SLC could indeed be related to the transfer case. The high mileage suggests potential mechanical wear within the transfer case gears themselves. Have you checked the condition and level of the transfer fluid recently? Insufficient or degraded transfer case oil can definitely cause shifting problems. Consider inspecting the transfer case oil for any signs of metallic particles, which would indicate gear wear.

Thanks for the quick reply! I haven't checked the transfer fluid myself, to be honest. Where exactly do I check that, and what should I be looking for besides the metal particles? Is it something a novice can handle, or am I better off taking it to a professional?

Given your experience level, it is advisable to consult a qualified mechanic. Draining and inspecting the transfer fluid, while seemingly straightforward, requires specific tools and knowledge to properly assess the fluid's condition and identify subtle signs of internal damage. Defective gears are a serious issue. A professional diagnosis will provide a definitive answer and prevent potential further damage.

Okay, thanks so much for the advice! I took it to the shop, and you were spot on. Turns out there was significant gear wear in the transfer case. They replaced the necessary parts and did a transfer case oil change. Cost me about 330€, but now it's shifting smoothly again! I appreciate the help!