It took me three 6 hour days to do the one on my E320. Replace the front seal of the tranny while in there and the flex disk at the front of the driveshaft while it is apart too. Nothing real complicated about it, just hard work. Don't forget to put a little oil on the new seals prior to pressing them in. I feel 99% sure that mine started leaking because I slightly overfilled the oil during one of the changes. I will not do that again
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