2002 AWD Venture Rear Turning GROAN noise

My 2002 AWD Venture ~47k "groans" when doing slow turns, such as parking lot maneuvers. It started only on humid days, and we used to joke about the groaning 'dead guy' in the back, but now it happens regardless of weather, and it has gotten louder.

The sound is similar to a tire rubbing in the wheelwell but it sounds more like it originates from the center of the rear where the differential would be on a conventional (non-AWD) vehicle. I checked underneath and there are no indications of rubbing anywhere, and the undercarriage is quite clean and not corroded.

No idiot lights are on. The brakes and rotors, as well as tires, have been replaced in the midst of this with no effect on the noise. Wheels appear solid...no 'real' loose bearings that I can tell as a layman.

Is there special AWD fluid I should check (no signs of leakage - all is crisp and clean) ...or maybe something electrical that may not be controlling the rear AWD module correctly?

Other ideas?
thanks

My 2002 AWD Venture ~47k "groans" when doing slow turns, such as parking lot maneuvers. It started only on humid days, and we used to joke about the groaning 'dead guy' in the back, but now it happens regardless of weather, and it has gotten louder.

The sound is similar to a tire rubbing in the wheelwell but it sounds more like it originates from the center of the rear where the differential would be on a conventional (non-AWD) vehicle. I checked underneath and there are no indications of rubbing anywhere, and the undercarriage is quite clean and not corroded.

No idiot lights are on. The brakes and rotors, as well as tires, have been replaced in the midst of this with no effect on the noise. Wheels appear solid...no 'real' loose bearings that I can tell as a layman.

Is there special AWD fluid I should check (no signs of leakage - all is crisp and clean) ...or maybe something electrical that may not be controlling the rear AWD module correctly?

Other ideas?
thanks

I do not know how the AWD works on a Venture, but I have had 4WD for many years, and I guess the Venture does not have a transfer case.
So it most be controlled electrically, and I would think that it is due to moisture that it started to groaning, because your AWD is connected all the time.
I had a FORD explorer once, it would not disconnect the front axle after I had the transfer case in 2WD, so it was groaning in this case.
So I think you are in AWD constantly, that would make that noise.
Larry

Larry:

Thanks for the reply. I have an Explorer too...and it is very easy to tell when it is 4WD vs 2WD. This 'groan' is different from that; it isn't a whine like power steering or a gearbox 'hum'.

The closest similar noise is sincerely like a Halloween toy that makes a ghostly "ooooooooh" as someone in pain. When I first heard it, I expected to find that the sidewall of a rear tire was somehow rubbing something.

The Venture does not appear to be in AWD during the time it makes this noise. The VersaTrac only kicks in to put power to the rear wheels when the front wheels begin to slip. I'll try to see if there are any indications that the AWD is not disengaged.

As for moisture, the car hasn't been flooded at all, and is garage-kept. I'll keep that in mind when I look at it again or check the rear drive fluid.

Thank for your help as I continue to investigate this. I can't afford to rack up hour at the dealership service center.

Tom

Larry:

Thanks for the reply. I have an Explorer too...and it is very easy to tell when it is 4WD vs 2WD. This 'groan' is different from that; it isn't a whine like power steering or a gearbox 'hum'.

The closest similar noise is sincerely like a Halloween toy that makes a ghostly "ooooooooh" as someone in pain. When I first heard it, I expected to find that the sidewall of a rear tire was somehow rubbing something.

The Venture does not appear to be in AWD during the time it makes this noise. The VersaTrac only kicks in to put power to the rear wheels when the front wheels begin to slip. I'll try to see if there are any indications that the AWD is not disengaged.

As for moisture, the car hasn't been flooded at all, and is garage-kept. I'll keep that in mind when I look at it again or check the rear drive fluid.

Thank for your help as I continue to investigate this. I can't afford to rack up hour at the dealership service center.

Tom

Hi Tom
it sure sounds like a ghost to me, sorry I couldn't help more.
Avoid dealership as long as you can, I'm sure you get to the bottom of the problem, hey, why don't you try Tom & Ray cartalk http://www.cartalk.com/, I listen to them every saturday online, they are great fun, and they always have a solution.
Larry

Did you find out what was causing your noise? I took our 2003 venture awd van into a dealer today for the same kind of noise. When we turn it makes a groaning noise in the rear. They took it apart and called gmc and were told the rear fluid was bad and that they have produced a new fluid that will make it not groan. The cost was $198.00 just for the fluid. We were told it is not covered under our extended warranty but considered maintainence. My thought is if they know the fluid that was put in when the car was made is faulty, so they had to develope a new fluid, shouldn't that be considered under your warranty? We decided not to have it fixed and are going to write to GM. Anyone else have this problem???? Thanks,

My 2003 Venture AWD has the same noise. It started at about 45000 miles, very faint. Now at nearly 50000 miles, it is annoyingly loud. My van is also clean underneath. No leaks, no rub marks.

The noise description is accurate. On my van, it occurs when the drivetrain is at operating temperature (after driving a while). If I park the vehicle a couple hours, its first few turns are quiet. The noise is equally loud when turning either direction and is not a constant pitch.

I am looking for help to solve this problem.

My 2003 Venture AWD has the same noise. It started at about 45000 miles, very faint. Now at nearly 50000 miles, it is annoyingly loud. My van is also clean underneath. No leaks, no rub marks.

The noise description is accurate. On my van, it occurs when the drivetrain is at operating temperature (after driving a while). If I park the vehicle a couple hours, its first few turns are quiet. The noise is equally loud when turning either direction and is not a constant pitch.

I am looking for help to solve this problem.
I have a copy of the gm bullitan about this noise. It is Document ID#686098 2003 Chevrolet Venture-4WD Noisy on Turns. I just emailed Chevy today, haven't heard anything yet. I will let you know if we find out anything also. My van noise is identical to yours. Only does it after it is warmed up. Thanks,

I fixed the groan by replacing fluid in the Rear Drive Module (RDM). Versatrak fluid costs about $26 per 500 ml (pint). RDM fluid capacity is 2 liters, so 4 bottles is sufficient.

After changing fluid, I drove one mile and then performed tight-circle turns, both directions; the noise was not yet fixed. It disappeared within 100 miles of additional driving.

I found relatively little information on the Internet about groan pertaining to Ventures. But searching a more general phrase like "Versatrak fluid" indicates that many Aztek owners experience the same problem.

I had the same problem on my 2002 AWD Oldsmobile. Started at about 45K miles. Sounds like a power stearing pump when turn to the extreme. After taking it in 3 times, they finally got it right on the 4 try at 62K miles. Fortunately it was under warranty when I was in the first 3 times (extended 60K for Oldsmobiles) and cost me nothing. I was starting to talk buy back. Then ended up replacing the complete rear differential. Probably because the fluid was bad. Big bucks I'm sure, I didn't see the actual cost. If you're not under an extended warranty, replacing the fluid is the best/cheapest way to go. Hope you're able to fix it before have to lay out the cash for a complete rear end.

If anyone has changed the fluid themselves in the Versatrak system, could you please let me know how difficult it is. I have not been able to find any information on it. I was wondering if it's as simple as a drain plug and a filler plug in the unit, how much room there is to work on it, and if I need any special tools. Any help or links to information would be greatly appreciated!

P.S. The local dealer wants $500 to do the job, crazy, so that's why I would like to do it myself if possible.

Thanks!
Art

Has anyone changed the fluid themselves in the Versatrak system?

I ended up changing the fluid myself, was not too hard, but I used an Amsoil product called "Severe Gear 75W-90W" oil. It worked great and much, much cheaper than the GM stuff. After changing the oil, I did the multiple tight circle turn maneuvers in both directions, and the "groan" went away. Here is the Amsoil web site, and here is the message they sent to me when I inquired about using their product.

http://www.amsoil.com/ (http://www.amsoil.com/)

Email reply Amsoil sent to me:

Thank you for contacting AMSOIL with your concerns.

In response to your inquiry, the Severe Gear 75W-90 Gear Oil is recommended to use for this application (product code SVG). It already has the additional performance additive formulated in it.

Thank you again for the opportunity to respond to your concerns. As always, please feel free to contact us again if we can be of further assistance.



Darryn Wallace

Technical Service Department

AMSOIL, Inc.