Weird Vibration/ grinding

[Beolarch]

I have this vibration that has arisen in the floorboards and have had multiple inspections done to my '96 grand cherokee w/ a 5.2L and quadratrac in it. I know its not the brakes, or my tires, alignment, balancing, and when went to the tranny/ driveline shop had them look at every thing on the outside along with fluids, and they said my driveshaft, and transfer case looked ok, but have a little leaking from the from axle. the leaking is very little and ive only had to add fluid in about a month(only a little top off). The shop did say my ring and pinion were starting to wear out due to excessive gear noise, and im not sure that is the cause of my vibration. The grand has 105,000 miles on it and is in pretty good shape, new tires, tune up, all new fluids. If anyone has any answers or ideas i sure could use some help, the dealership tried to tell me it was my front driveshaft needing to updated to a different design, (cost around $1000) but i just about laughed at them, and figured if it was that big of a problem, it would be a recall. The vibraton starts around 25, and just gets worse the faster i go, slowly getting worse. Any help is greatly appreciated.

[Cam7]

Check the axle cv joints and chek the drive shafts again. Drive the Jeep to about 60 and put in nuetral and check if you still have the Vibration while coasting.

[cdlabelle]

Ben, maybe we can work on resolving this problem together....See my post lower down the page called...........grinding Sounds. I'm stumped too.
My next step it to remove the drive shaft from thransfer case to front axle. There's a a double cardan u-joint on the transfer case side. I'm hoping it's one of those yoke's that are faulty.

[Beolarch]

The driveline shop said my cv joints were good, and the boots on them are in really good shape, no signs of any serious rubbing or cracking, so that doesn't seem like it would be it, there is a little play in the shafts when spinning them, but everybody ive called about the problem says that that is a normal thing for grand cherokees. The grinding has gotten slowly worse and now i can feel it around 20 mph. Also i tried to pull the driveshaft out but was stumped with that 6 bolt design on the front end, didn't want to risk making the car un-drivable, so i just pulled the end with the double cardan and tried to wiggle tings around, but everything there checked out ok too. I think its possible that by pinion bearings have worn down a lot due to the wear on my ring and pinion, after all the shop did say that those were pretty worn. and its possible the gtrinding is coming from there. At least im hoping, and hoping its not in my t-case cause i had to have one rebuilt on my old 90 yj and that was a ordeal in itself. Thanks for the replies, i'll keep checking back to seeif anyone comes up with anymore ideas or answers.

[cdlabelle]

Ben....see my latest post in .......grinding Sounds

[Cam7]

Try Jacking all 4 wheels off the ground and secure with Jack Stands. Start the Jeep and put it in gear , You should be able to Isolate the noise. Might even chech for a bad hub.Try removing the front drive shaft like cydlabelle said and try using a stethascope on the Diff.

[cdlabelle]

Ben....and others with grinding differentials..
I was searfin da net and came across these web sites, but the last pfd document is about rebuilding Dana 30 Diffs right from Spicer.

www.shafts.com/parts/yukon-instructions.pdf

http://www.tpub.com/content/construc.../14273_197.htm

www2.dana.com/pdf/X5001-CVSP.PDF (just cut/paste this link)

enjoy the reading.....cdlabelle

[dream716]

Originally Posted by Beolarch

I have this vibration that has arisen in the floorboards and have had multiple inspections done to my '96 grand cherokee w/ a 5.2L and quadratrac in it. I know its not the brakes, or my tires, alignment, balancing, and when went to the tranny/ driveline shop had them look at every thing on the outside along with fluids, and they said my driveshaft, and transfer case looked ok, but have a little leaking from the from axle. the leaking is very little and ive only had to add fluid in about a month(only a little top off). The shop did say my ring and pinion were starting to wear out due to excessive gear noise, and im not sure that is the cause of my vibration. The grand has 105,000 miles on it and is in pretty good shape, new tires, tune up, all new fluids. If anyone has any answers or ideas i sure could use some help, the dealership tried to tell me it was my front driveshaft needing to updated to a different design, (cost around $1000) but i just about laughed at them, and figured if it was that big of a problem, it would be a recall. The vibraton starts around 25, and just gets worse the faster i go, slowly getting worse. Any help is greatly appreciated.

I had this problem with my '96 and it sound like it came from the left Hub but it turned out to be a bad right Hub.