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View Full Version : NOT tires growling...


h2oskibumz
06-30-2008, 11:29 PM
OK, I'm going to come off sounding like total goof, but my 3500 is the heaviest truck I've had, and it is my first diesel.

I have been chasing a front end growl for the last couple of months and have not yet found the cause.

It started out as being fine (normal, quiet) under throttle, and only noisy when coasting... that led me to the point where I was thinking CV or U joints, but they are all tight... as the problem has gone on for several weeks it seems like it has the growl most of the time now, even under load/throttle.

It is not front wheel bearings, the cv shafts seem solid, not the front differential... and I would have SWORN it was forward of the Xfer case... but I now think I was wrong about that.

I think I stumbled across it tonight. I was routing a pair of 2 gauge wires from the 2nd battery down under the truck and up trough the floor for an inverter under the rear seat. There is some sort of carrier bearing around the front half of the rear driveshaft, right at the back of the cab... that rubber bushing/bearing is shot and the shaft can move about within the bracket where this rubber resides. I had checked this when I checked U joints probably 6 weeks ago and it seemed OK then, but... now there is definitely more play here thant here should be.

Can someone point me in the right direction on the appropriate terminology for this? I presume it is replaceable and a job that can be easily managed, has anyone else seen this or replaced this item?

Finally, do the knowledgeable folks here think I'm on the right track here or am I smoking crack??

Thanks!

blksmok
06-30-2008, 11:35 PM
What you are looking at is the carrier bearing... The problems usually start out with a shudder under initial acceleration. Have you felt a shudder while leaving from a dead stop? Sounds like you are on top of it, but I've never changed one myself... Maybe someone else will chime in and tell you what it takes.

h2oskibumz
06-30-2008, 11:45 PM
Thanks Dave!

I THOUGHT it was the carrier bearing, but I wasn't sure it that my teminology was right.

No shudders... no vibrations. The fact that it initially seemed to happen during coast low/no power situations had me convinced it was a U joint, but I couldn't figure out why there was no vibration.

I'm pretty confident this is the culprit.

Sure sounds like I'm running off road tires on the front though, and I KNOW those Michelins are quite!!!