I could really use some advice for a friend about a drive train issue
 

A friend who has had his 190e much longer than I have had mine is in a jam. He has some sort of noise coming from the rear when he steps on the gas from a standstill. Once the car is moving it drives fine. I'm guessing that it might be a rear axle issue or a u joint issue. He is frustrated and wants to junk the car. He thought it was the transmission. I told him let me look in to it before you do anything rash. Does anyone have any ideas what could be going on?

What sort of noise? A clunk?

That is a good word for it. A slight grind/hesitation with a clunk when starting from a stop. No noise once the car is moving.

There are numerous rubber bushings throughout the rear suspension and differential area, along with flex discs on the driveline. Any one of those that has deteriorated is a candidate for causing clunks.

Thanks for the reply. What a pain in the neck this could turn out to be.

Best description...is it a clunk or a 'ting'? At low speeds blip the throttle really quick. Does it do it again? If so. Flex disk for sure.

Seems like a clunk and some hesitation than snaps in to place when going from a complete stop to stepping on the gas from what I remember. I will get back to you on that

I agree, my '93 190 made a heck of clunking noise at take off when the right rear sub-frame mount bushing went bad. Then later, the front flex disc went out and also made clunking noises.

But it isnt only a clunk. The car has a hesitation and then like a small grind noise before it locks in to move. Only happens when stepping on the gas from a full stop. Doesnt happen while moving

I cant get under the car yet because we dont have the right kind of jack. I did take some pictures though. I cant tell if the disc is bad from the pictures. I will post what I have so far. He also did tell me he sometimes would hear a small thud when making slow right turns. I saw some oil/grease on the axle but its not wet. He has a oil leak up front so I think that may just be accumulated oil/dirt that blew back over the years while driving. His front disc was changed 50 or 60k miles ago. I dont know if his rear disc was ever changed. It may have been. I think he is around 165k now

Could it be the shaft, the axle or some sort of bearing?

Some more pics

Maybe the key isnt the clunk? Maybe the key is the hesitation and sort of grind noise that comes before the car moves.

Be sure to also check the front flex disc. Does the transmission go into drive smoothly with no hesitation? When was the trans. fluid and filter last changed?
Has the differential fluid been checked or changed?

Can I check the front disc visually without the car being on a lift?

It seems to stick or grind a bit when starting in first gear from a stop. I noticed the rpms go up till it seems to snap in to place. The clunk sound seems to come from the rear though. Maybe they are not directly related? I couldnt tell if there was anything wrong with the rear disk visually by sliding under the car. Isnt there some sort of drive shaft bearing? Could that be the cause?

The front disk was changed aroound 50k miles ago. The tranny fluid and filter around 40k miles ago.

If the car seems to drive ok when not starting off in 1st gear from a complete stop would it be crazy to drive it 10-15 miles to a mechanic?