Rear Differential Causing Vibration? Need the experts!!

[rtp03]

On my 92 TSI AWD my rear diff has a 1/4 inch rotational play. Should be a lot less. Would this problem also cause my car to vibrate in the body at cruising highway speeds? No vibration at all in steering wheel and it only vibrates when barely on the gas. Things I have done to eliminate the vibration with no luck are:

- New rims and tires and balanced wheels - vibrated before and after this was done

- New Axles and wheel bearings in front

- Rebuilt transmission - vibrated before it was rebulit and still does

- New motor mounts on left and right side

Any help would be great!!

 

[Defiant]

Driveshaft carrier bearing? U-joint?

http://www.geocities.com/qwik93awd/Vfaq/rearendthumpfix.htm

http://www.plymouthlaser.com/shaft.htm

http://www.plymouthlaser.com/dshaft.htm

Or, have the dealer check your transfer case.

 

[rtp03]

Both hanger bearing s for the driveshaft and U-joints are all good.

Transfer case was replaced and still is good.

 

[DSM90AWD]

My 1Gs diff has 6-7mm of lash (limit is 5mm).. also has the clunk on shifting. I'm thinking this is what's been eating up my rear CBs.

The other day I pumped it full of silicone hoping to at least cure some of the "clunk". Well it did.. but now I have a light vibration felt from 35-40mph. I assume that now that the rear CB is more/less solid.. it's ability to absorb vibrations from the rear diff was defeated. Now they are transmitted thru the chasis

so guess it's $55 for a new CB.. and shop for a new diff

 

[rtp03]

I replaced the rear end with another and the vibration is still there! I still get it when light on the throttle between 3k and 4k in 4th or 5th gear. Let off the gas and it goes away. Let in the clutch and it goes away. Replaced the axles also and front wheel bearings. Tranny was just rebuilt and had problem before and after.

Could it be a simple as the exhaust vibrating. It seems like all mounts are on though?

Any more ideas??

 

[tsitalon1]

I replaced the rear end with another and the vibration is still there! I still get it when light on the throttle between 3k and 4k in 4th or 5th gear. Let off the gas and it goes away. Let in the clutch and it goes away. Replaced the axles also and front wheel bearings. Tranny was just rebuilt and had problem before and after.

Could it be a simple as the exhaust vibrating. It seems like all mounts are on though?

Any more ideas??

Did you ever get this resolved? I have same issue and for the love of god I cannot isolate it.

James

 

[kicknurass4fun]

Ya I have the same problem. I thought for sure it was my u-joints and carrier bearings so i just replaced those. It helped with some of the noise but not all of it. When i was replacing the carrier bearings and the ujoints i thought the rear end seemed to have quite a bit of play in it. When rotating the diff clockwise to counterclock wise measuring for the circle on the diff where the drive shaft bolts to. I measured a little over 1 cm of play. Does this mean the its time for a new diff? Does anybody ever just rebuild the old ones? If so how much does it usually cost? Thanks
Lou

 

[DSM90AWD]

I measured a little over 1 cm of play. Does this mean the its time for a new diff?

1cm is alot as service limit is 5mm!
Be sure to measure it with the parking brake engaged.

Does anybody ever just rebuild the old ones? If so how much does it usually cost?

I've heard rumours of certain DSM Shops (Buschur namely) taking on this type of job, but would check with them directly. If you asked locally (e.g. a tranny shop) you will likely be quoted >$1000 for parts/labor so prol a better deal to find a good used one ($300-450 is the going rate for a complete 4-bolt / $100-150 for a 3-bolt).

I'd definitely shop for one near you so can test the lash before purchasing