Random whining noise from the rear

[Archaelas]

Over the last week or so, I've noticed this random whining noise coming from the rear of my T/A. It only happens either in reverse or above 65mph. Up until this morning, I had only heard it in reverse and only periodically. It was almost more like a groaning noise than whining but this morning I hit I-75 on the way to work and notice it again but higher pitched and constant. In reverse, it's low pitched and seems to come and go, almost cyclical.

My thoughts so far are either the diff, a wheel bearing or the parking brake not fully disengaging (which on that note, I have to pull the parking brake ALL THE WAY in order to keep the car from rolling if the nose is pointed downhill). Any other ideas?

[WS6S]

first thing i would try is changing out the gear oil in the rear,make sure if you do that you add the posi lube.while she,s jacked up check for any play in the outer bearings.can you take the rear cover off and look around ?

[WS6S]

as for the parking brake,maybe its time for a set of em ?

[Danger731]

Over the last week or so, I've noticed this random whining noise coming from the rear of my T/A. It only happens either in reverse or above 65mph. Up until this morning, I had only heard it in reverse and only periodically. It was almost more like a groaning noise than whining but this morning I hit I-75 on the way to work and notice it again but higher pitched and constant. In reverse, it's low pitched and seems to come and go, almost cyclical.

My thoughts so far are either the diff, a wheel bearing or the parking brake not fully disengaging (which on that note, I have to pull the parking brake ALL THE WAY in order to keep the car from rolling if the nose is pointed downhill). Any other ideas?

Let me guess, M6 ?

[c5z28]

comes and goes sounds like the ring gear or carrier is walking
Nothing like taking it apart and looking at the wear patterns.

[Archaelas]

Let me guess, M6 ?

Yep, M6 .

as for the parking brake,maybe its time for a set of em ?

Brakes are scheduled for this weekend. Parking brake had this issue back in Feb last year when I bought it, turned out it was loosening itself but the shoes were fine then but are being checked again this weekend. I'm fairly certain that it's come loose again though.

first thing i would try is changing out the gear oil in the rear,make sure if you do that you add the posi lube.while she,s jacked up check for any play in the outer bearings.can you take the rear cover off and look around ?

comes and goes sounds like the ring gear or carrier is walking

Good thoughts, I'll take a gander under there while she's in the air for the brakes anyway. Never actually changed the gear oil or anything like that before so any pointers in that department would be much appreciated.

On another note, I noticed yesterday that it does it (very faintly, I had to hang my head out the window and idle to hear it) when I turn at low speeds. Doesn't do it at higher speed (15+) that I could hear anyway.

[WS6S]

fluid change with posi lube additive.

[twozs]

fluid change with posi lube additive.

if its not the optional auburn rear that slp installed (which might not need it either,just not sure) the zexel torsen rear does not need any posi additive as they have no clutches...... Zexel Torsen (Worm Gear Driven) Differential Technology

Pros: Cons:
Never needs replacing once installed
No need for a limited-slip additive
Instantly transfers torque, no wheel spin
Is the latest technology in differentials
Can be fragile; 500ft/lb torque limit on OEM units
Generally more expensive than other differentials
Expensive Upfront cost
Not available for all applications as of 2002

[twozs]

the auburn rear does need GM lubrizol additive

[HOBS]

Sounds just like the Zexel-Torsen rear in my car. The general opinion from 3 dealerships was that my rear-end was fubar. But you might be luckier than me.

[KMdef9]

Mine whines as well, been told by 2 other people (who know cars), my rear end is on it's way out.

[WS6S]

who knows it could be the dumafletcher,or the doo du doot or maybe even the finnigan pin ?

[Cutlass]

if its not the optional auburn rear that slp installed (which might not need it either,just not sure) the zexel torsen rear does not need any posi additive as they have no clutches......

The GM LSD additive is actually recommended by GM for these Zexel diffs. It has also been used to cure the "rusty screw" Torsen noise.

[twozs]

what do i know, mines fine after cooking an outer bearing and replacing the bearing AND axle under warranty an they only used the gear lube no additive 25,000 miles ago and 2 years

[Cutlass]

There really isn't anything wrong with leaving it out. Its just a friction modifier to eliminate noises and clutch shuddering. Some synthetic gear lubes have it built in.

[WS6S]

There really isn't anything wrong with leaving it out. Its just a friction modifier to eliminate noises and clutch shuddering. Some synthetic gear lubes have it built in.

when i thru my 4.10,s in my car i added lucas synthetic gear oil drove it a few hundred miles and when backing and tight turns she squeeled.ripped it apart checked it all out put it back together as everything was fine except for some axle shaft wear. reused the lucas and added posi lube and no more noises out of her smooth as a strippers ass ( well some strippers ).

[twozs]

There really isn't anything wrong with leaving it out. Its just a friction modifier to eliminate noises and clutch shuddering. Some synthetic gear lubes have it built in.

but the zexel torsen doesn't have clutches so thats why its not needed,right? and as a side note i "heard" that using synthetic lube in the auburn rear is a horrible no no and can really do some damage. ill try to find out where i heard it

[Cutlass]

but the zexel torsen doesn't have clutches so thats why its not needed,right? and as a side note i "heard" that using synthetic lube in the auburn rear is a horrible no no and can really do some damage. ill try to find out where i heard it

Thats what I always thought, but apparently there are some high frictional forces in the zexel torsen rear that can cause some noises. Like the "Rusty Screw" noise.
Google "rusty screw torsen." That should bring up some info to read.

[djkremer]

Hello all, new to the forum and joined specifically because of this topic.

Is there anyway just by looking which rear the car has?

My car has the whining sound ALL the time, not just when turning and it has gotten worse over time. Not long after I got it I changed out the oil in the diff and didn't know about the GM additive. It kills me, the car only has 27,xxx miles on it.

I plan on changing the oil again within the next week with the additive and I will post my findings.

[Cutlass]

If its stock and untouched than you have a GM 7.5"/7.625" 10 bolt. To find out what gear ratio, open the door and look for this sticker:



Rear end gear ratio RPO codes
2.73's (GU2) for autos
3.23's (GU5) for autos
3.42's (GU6) for M6.

and G80 means Limited Slip