While driving my car in the summer it had a rear clunk sound when i started off. I thought my front diff mount was busted, but it seems fine. I did find that one of the two rear sway bars was missing a nut to hold the braket. Therefore it was able to move. Could this be the cause the the clunk? or should i contiue looking?

Also does anyone have a pic or explained the way the diff is mounts? The diff has two rear mounts, these mounts have a peice that looks like a crown. Which way does the crown face? and is it below or above the actual diff mount?

 

There's actually three mounts; the two rear ones you're talking about, and there's a front one that is kind of hard to see. I had the same problem with my '87, and I thought it was the two rear ones because I ordered the bushings from the dealer and they said at the time that those WERE the only mounts for the differential.

Well, I got it all apart only to find out that indeed there is a front mount, and mine was torn in half, allowing the differential to flex upwards when power was applied. I ordered the front mount and two days later my problem was solved.

The mount I'm talking about is kind of rectangular in shape, maybe 3 inches by 4 inches in size. If you look hard, you can see it mounted on the very front of the differential housing.

I'm going to look on my EPC in a minute and get you an answer on the rear crown mounts

 

I believe the crown faces down because the rubber bushings go in from the top down. My EPC does not show the "crown" part of the mount, but if I remember right that's how it goes...it's been a couple years, so someone correct me if I'm wrong.

 

Sorry forgot to mention i check the front diff mount and it looked good. I just am unsure how to check the condition of the other ones. They seem fine, but there was a clunk so something isnt right

 

unless you've had the diff off or you had the car up on a hoist to put the force against the front of the diff, it might be hard to tell if the rubber cracked cause it's pressed between the diff and bracket on the subframe.

 

my whole rear subframe is off. Redoing the busing so everything is taken apart

 

Intrusting I here a slight clunk noise when I let off the pedal in low rev I always thought it was tranny shaking or something like that

 

i went thru 2 of the stock diff mounts that hook up to to the cross member with in a year in my N/A, then i bought the mazdacomp mount and never had a prob again, oh yeah the crown is supposed to point up.

 

If the front is good but the rears are bad, I wouldn't think that there'd be too much of a clunking noise because of the fact that the front is still held in place. Also, for both to go bad at the same time? It would be difficult to check if they were bad like RXciting said because you can't get to them until you take out the differential.

I still think there's something else needed here, but I don't know what...if the front is good, and assuming the rears are good, and all your links are tight and so forth, I have no idea. My experience has taught me that the front mount is bad, but it's a bitch to replace, so I hope that you find something else wrong.

Just a thought....could it be the internals of the LSD unit.............?

 

It was the differential mount on mine, and its wasn't easy to see. If you are sure yours isn't broken, then I'm not sure what it could be. A squirrel stuck in your driveshaft maybe?