rough gear shifting & sagging rear suspension

[BenzDslPwr]

Hello everyone,

I am an absolute newbie on this forum. Prior to registering, I have read some of your threads and I was truly impressed with everyone's knowledge. I am hoping that I will expand mine during my membership.

So, this is something that I have been dealing with for the last 4 months now. I am suspecting that some of these problems have been widely covered on this forum, however, all these issues started happening pretty much at the same time. And I think it is worth mentioning.

My MB: 1985 300SD - 170K miles, mostly city driving

- suspension (?) - just recently, I noticed that my rear end is sagging a bit. 90% of the time I drive by myself and hardly have any passengers. So, when I sit 2 adults in the back, the rear end goes down so much that my exhaust pipes grind against the ground when driving on uneven surface.

- transmission - gear shifting has been inconsistently rough lately (changing the fluid and the filter did not change anything). Going from 1st to 2nd has been rough to the point that I can feel a significant jerk. Going from the 2nd to 3rd gear is much better, however, I can hear a slight thud.

- during quick acceleration, then letting go off the pedal and then breaking to a complete stop, a loud thud in the back is noticeable. The same thing happens when I accelerate and quickly let go off the pedal during city driving.

- when putting into Reverse, I can hear a thud in the back plus the whole rear end 'jumps up.'

I am thinking that there could be different things that are happening at the same time. Has anyone had similar symptoms with their cars? What possibly can be causing these things all of sudden. Any feedback will be greatly appreciated. TIA.