Slop in the rear?
 

My 99 e300 with 430k I just got on the road (426k) I am hashing out problems with it that were wrong with it before parked. Anyway, to cut to the chase. When shifting to drive the car jerks and jolts noticeably. Is that ring and pinion war I am feeling? It feels different than the other two cars with less miles. Replaced the front flex disc, center support bearing and rear flex disc were crack free and center support had minimal play if any.

I plan to replace the fluid in the rear.

Final Drive Slop
 

Usually if the final drive it loose it will make a clanging sound as the looseness gets taken up .

Maybe look at the drive half shafts ? .

look at the linkage which limits for and aft movement of the wheel?

I have this issue in a 300cd , well over 500k now . It can be that large pin that can get the wear , the slack if yours is like mine , just may require a professional service tech , you’ll have to get the rear of the car up and have it in neutral . I do all my own labor so theirs that to contend with for safety . Move the yoke of the differential and feel for slack in the engagement back and forth . It’s that pin that’s worn . Since you’ll need labor , new parts , the cost can climb . I’ve chosen to pull one out of a yard that’s good , just waiting to do this very messy job . It will feel like a different car once done .You can call around for the fix , maybe someone has one sitting around at their shop . Some older European shops hold on to good used parts just because Mercedes last like no other .

“Play differential w123 “ , search that heading on YouTube , will give you a look at this problem

Thanks guys I am going to look into it. Have no experience with diffs other than fluid services. Or one exploding and a swap from customers having a leak and never fixing it. Lol

An issue I have found is the transmission yoke locknut getting worn… car will lurch after a few seconds when leaving the line…