My wife's 91 300TE (128k miles) is leaving a small pool of oil on the garage floor. The dip stick shows a lost of 3/4 pint in the last 2k miles. I had it up on a lift today-oily mostly around the rear of the bell housing. We cleaned up the oil with degreaser and I drove the car around all afternoon and had it back up on the lift and it seems like the oil is coming out of the bottom of the bell housing. We pried the plastic inspection cover of the front of the bell housing and felt oil inside the bellhousing. My (non MBZ) mechanic says it might be leaking from the rear main seal.
1. I am going to fix this but is it something I need to do right away?
2. Is it really the rear main seal or could it be something else?
3. If it is indeed the rear main seal, (I am a more or less shade mechanic) is this something I can do myself?
TIA for any comments.