1983 Mercedes 300SD Problem

Hello everybody, my names Daniel and i just recently got this car about 1 month ago from a used dealership. My problem is that when i press on the accelerator either a 1/4 or more down i get a horrible vibartion coming from my rear when the car is going between 15mph and 25mph, you can feel it even more with the more you press on the gas. It sounds like a thumping, rumbleing sound that might be coming from the back tires. But after i pick up speed it stops making the horrible sound. And also when you light press on the gas and slowing picking up speed you cant hear the sound. I just got the car not that long ago and gave it an oil change (2 times cuz the oil was so damn black, i guess that happens to diesels. Anyways i might have pushed the car to hard by pressing the gas to much and even starting it in 2nd gear and punching it (I wanted to hear that turbocharger roar) I think thats where i went wrong, now im getting that noise, and worrying that it might by my tranny, or something in my rear end. Can someone plz help me find out what my problem is, I dont think that it might be major cuz i added more AT fluid and the Gunk* bottle to clean the AT fluid etc. And its not that loud anymore (i think). I dont know about the previous matience but the engine sounds fine (but it sounds like it needs a timing adjustment but I might be wrong, it revs at 33-3500 at 80mph.

Can somebody plz help me out?

I have a 1983 300SD that was producing a loud thumping noise at low speeds and seemed to go away as my speed increased. I thought it was the injectors. I jacked the car up put it on jack stands and started looking under the car. I found out that it was the driveshaft support bushing. The rubber was chewed up and was allowing the driveshaft to vibrate causing a tremendous thumping noise.

I bought the bearing and support bracket. Spent about 2 hours under the car replacing it and now it runs perfect. Inexpensive parts $50 -$70.

I would check this on your car. Also while you are under there check the flex plates at each end to see if they were damaged or cracked. If so replace them also.

Easy job if you have a lift. Time consuming if you are on your back in the driveway like I did.

i have had the CV joint on rear passenger side produce a rummbling noise on my 300 td, that would go away at speed.
Abuot an hour on my back easy to remove & replace , 2 small bottle jacks is smokin. :smokin: