I have a clanking noise coming from the differential area. It only happens when I shift(including first). I think there my be too much play at the point where the driveshaft connects with the differential.
If I'm right what are my options?? New diff and driveshaft?? What would be the best differential for top speed??

Are you talking about while moving the gear selector while the car is standing still? Or while the car is moving and shifting?

There are a lot of things that can cause clunking/clanking.

You need to get the car in the air and start looking. Remember that noise can be transmitted through the drive shafts.

Check your: trans. mount, front flex disc, center carrier bearing, center carrier bearing mount, rear flex disc, rear diff. mount and axle shafts. Pushing and pulling on the drive shaft front, center and rear can tell you a lot. Look for cracking rubber in any of the mounts. If it is heavily checked... Replace it.

The shafts could be a possibility if the boots are compromised. Common issue for 20+ year old rubber parts.

Also, if you diff. is leaky and ran low, it could be an internal problem within the diff. IE: worn bearings or gears. Check to see if you have any play at the pinion bearing and check the fluid level in the diff.

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AJ

1985 300D (SOLD)

^^Good advice.

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83 SD

84 CD