driveline whine, dealer cant fix

OK, i've posted about this before diff whines between 55 and 70 mph. Over the last 6 months its been back to the dealership 9 times, they've rebuilt the rear diff 3 times, the last time installing a whole new final drive assembley, they've replaced the transfer case, they've done a host of other things too including removing the front drive shafts and that was the only time the noise went away.

Isuzu rep has driven the car, isuzu engineers have been directing the attempts to repair, they now have 4 engineers trying to come up with what to do next.

The dealership have been very good, providing me with a loaner car when i've needed it, does anyone have any suggestions because i dont think Isuzu or the dealer know what to do next?

I guess new front diff or transmission?

Its an 01 with 53000 miles on it now, it had 46000 on when they started working on the problem.

Any suggestions greatly appreciated.

Pete

Pete - you said the noise is between 55-70, is it an under accel noise or a noise when coasting? I have this noise at the same speeds when my foot is on the gas, if I take my foot off the gas, the whine goes away. Had it at the dealer 2 weeks ago, they SAID they drove another one and it did the same thing. 1) I doubt they had another to drive, 2) I doubt it made the same noise (if they drove another one), as mine only started this recently. Haven't had time to deal with it further yet, but it would help to know if your problem was similar. Most people that have complained of a rear end noise (or a whine) here have had the problem when coasting.

I'm afraid that I can't help you with the troubleshooting, but I can say that your dealer RULES.

Others should take a lesson from them.
We should send the service department a card or some flowers.

just remove your driveline shaft and mail it to me, sounds like you no longer need it and it is deffective. I will make sure it has a good home. :p

I have a 2001 and it had a whiney rear from the start in coasting mode.
I complained and they replaced. It still whines.
I have conculuded that Isuzu has poor Hypoid gear cutting practice and that we just live with it. I am amazed the dealer has gone to such lengths considering the noise is very common.
Roy

The noise i hear is when coasting, if you feather the accelerator you can make it come and go, just as you accelerate or are coasting you hear it, when you back off it goes away.
Raque ....i would say definitely get it in while still under warranty, both my dealer and Isuzu have said its not right and needs to be fixed, so far my my guess its cost them upwards of 10 or $12,000 with no end in sight.

It does get annoying when you know the noise is there i find myself deliberately listening for it, it drives me crazy!

When we do finally figure it out i keep ya all posted, it would be nice to go into the dealership and tell 'em how to fix it!!

Good news is i know the guy at the rentals desk now pretty well, last week he fixed me up with a brand new pontiac grand prix GT loaner, way more fun than the chevy malibu classic i used to get, nasty, nasty little thing, should have been destroyed at birth!

Pete

Sounds like the transfer case... had mine replaced several times for this noise. If you install a TOD disconnect switch, it makes it very clear it is the tcase and not the rear end.

Tone,
I forgot to mention they allready put a new transfer case in the last time it was in, it didnt help, now they've ordered up a new front differential, should be in this week but i'm not real optomistic.

They also tried some other stuff and left me with a clunk in the driveline now every time i come to a stop.

I think if the front diff doesnt work they talked about replacing the transmission as thats about all thats left.

Pete

Here's a thought Pete.....
Have them check the alignment of the drive shafts and U-joints. If the shafts are warped or U-joints are bad you will get whineing noise also.
If they are both true and straight then the transfer case is the culprit,even though they have changed it one doesn't mean that the replacement is any good.
Good luck......John

since it's rear wheel drive, my best guess it's your rear pignon bearing . :(

John, i'll pass that along thanx, i guess a duff transfer case even though its new is possible, they were quite sure that that was the cause before.

I dont think its the pinion bearings as they were replaced with the new final drive assembly.

Your VX is not lifted, is it?

Have they tried disconnecting the TOD to see if the noise goes away? How about running with one drive shaft or the other removed? Oh nevermind, this is an Isuzu dealer - they'll do it the long, expensive way....

LOL....TONE you are so right !!!!!

I just had the 60K(even though I only had 56K on the odo)transmission fluid/filter service,Tire rotation/Balance, front wheel bearings repacked and front brakes replaced at the local shop I deal with (NON-ISUZU garage) for less than $300.00.

If it had been an Isuzu dealer it would have been around $1,000.00, I'm betting.
It pays to shop around I guess.
John ;)

Yal, no its not lifted, its completely stock, Tone...they did remove the drive shafts and it the noise did go away which is why they thought it was the transfer case and replaced it.

Its been in the shop for the last week while i was in San Francisco on vacation (what a cool place) so i feel very relaxed right now!! :) i'm just waiting to hear what happened from the shop manager .......will know more later!

Pete