Mercedes B Klasse Transfer Case Oil Wear

That sounds familiar. I have a similar B Klasse, although not the latest model, and had similar gearbox issues that turned out to be the transfer case. Get the transfer fluid checked ASAP. If it's low or burnt, that's a bad sign. It could point to defective gears in the transfer case itself. Have you noticed any oil leakage?

Oil leakage, interesting... I haven't specifically looked for that. Where would I be looking for the leakage? And how would I check the transfer fluid to see if it's low or burnt? Is that something I can do myself, or does it need special equipment?

Checking the transfer fluid level usually requires removing a fill plug, which can be difficult to reach on some models without a lift. The leakage would likely be around the transfer case seals or the housing itself. Honestly, with those symptoms, I'd suggest taking it to a workshop to get a professional diagnosis. Gear oil problems can escalate quickly and are not worth DIY-ing, unless you are sure that's the main issue.

Okay, thanks. I thought it might be beyond my skill level. I'll get it booked into a workshop and tell them to specifically check the transfer case oil wear, the transfer fluid and possible oil leakage. Seems like my initial suspicion of defective gears could be right too. They quoted me around 330€ for the repair, so hopefully that's accurate. Thanks again!