I recently performed a transmission service on my 2012. I noticed that the transfer case has a separate drain plug. The MB directions say to prefill the transfer case with 700 ml, but they don't say to drain it first. Everything I've read says that the tranny feeds the transfer case.

My questions are:

1. Am I correct that there is no front differential, that the front axles come out of the transfer case, and that the transmission feeds the transfer case?

2. Why is there a drain plug on the transfer case? What is the correct procedure to drain and refill?

3. Where is the fill plug for the transfer case that the directions refer to?

Thanks in advance for your replies.

 

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This what EPC shows...

 

My setup looks different. It may be that there is a differential forward of the transfer case. It has a 5 inch (approx) square plate on the bottom that is removable (hex head bolts around the perimeter) and a horizontal oil drain tube cast into the body with a hex head plug on the side. The front axles come out of the sides.

Unfortunately, I didn't take a picture.

The WIS printout that I have appears to include directions for refilling the transfer case after a rebuild, as it refers to pre-filling it with 700 ml of ATF.

I've read elsewhere that the front diff requires removal of an axle to refill.

Thanks again for your replies.