Accelleration Drivetrain Noise on 2004 Yukon AWD

[cornbuzzard]

Since I picked it up, my 2004 AWD Yukon has had a noise coming from the drivetrain during acceleration. Its most noticable after you hit 30MPH and beyond. It stops when you reach the desired speed and level off, or put on cruise. It sounds like a bearing or hydraulic noise. I will compare the noise to a quiet diesel motor, or a metal on metal sound like when a bearing is going out, or a distorted whistle, it hard to describe. Others have discussed this on here before. My dealer has replaced the thrust bearing and the front drive shaft with a balanced one, but it did not help. Someone else on here mentioned the carrier bearings. Are they in the transfer case? Thats where it sounds like the noise is coming from.

[cornbuzzard]

The noise on acceleration is like a whine/whistle noise. Anyone else got it? I heard it may be the carrier bearings? Already been to the dealer 4 times!

[Yukon1995]

Does it sound like a small motor? A buzzing...almost like a stereo wire crossed over something? I have that problem and it goes faster when I accelerate.

[cornbuzzard]

no, its definately in the drivetrain. just got it back from the dealer, they put microphone sensors all over the vehicle, and think they have isolated it to the front differential bearings. We will see, if it corrects it, i will post.

[SGunner]

Originally Posted by cornbuzzard

no, its definately in the drivetrain. just got it back from the dealer, they put microphone sensors all over the vehicle, and think they have isolated it to the front differential bearings. We will see, if it corrects it, i will post.

I recently purchased a 2002 Denali and it whines from the front end around the same range and when I take my foot off the accelerator the sound disappears. The dealer told me that its a normal noise due to the GM AWD system. No damage being done just have to live with it. Its annoying!

[realjoe2000]

Originally Posted by cornbuzzard

Since I picked it up, my 2004 AWD Yukon has had a noise coming from the drivetrain during acceleration. Its most noticable after you hit 30MPH and beyond. It stops when you reach the desired speed and level off, or put on cruise. It sounds like a bearing or hydraulic noise. I will compare the noise to a quiet diesel motor, or a metal on metal sound like when a bearing is going out, or a distorted whistle, it hard to describe. Others have discussed this on here before. My dealer has replaced the thrust bearing and the front drive shaft with a balanced one, but it did not help. Someone else on here mentioned the carrier bearings. Are they in the transfer case? Thats where it sounds like the noise is coming from.

I just purchased a 01 Denali XL with the identical whine. Sounded like it was in the transfer case area under the truck. It was there when I test drove it and they agreed to fix it before I made an offer. And low and behold it was a bad front axle carrier bearing. So dont let any dealer tell you it is normal, cause it aint. But the sound does come from under the truck. New differential bearings, and quiet as a mouse. Hope this helps.

[SGunner]

Originally Posted by realjoe2000

I just purchased a 01 Denali XL with the identical whine. Sounded like it was in the transfer case area under the truck. It was there when I test drove it and they agreed to fix it before I made an offer. And low and behold it was a bad front axle carrier bearing. So dont let any dealer tell you it is normal, cause it aint. But the sound does come from under the truck. New differential bearings, and quiet as a mouse. Hope this helps.

Thanks Joe.

Well I found a service bulletin from alldata.com regarding "Whining from the Front Axle" and I sent it into my dealer. They agree this could be a possible fix but no gaurantee. They have to replace the front Propeller Shaft under warranty this Wednesday.

I'll post the aftermath and hope that this fixes it.

Otherwise I'll keep the carrier bearings in mind. Thanks again!

[SGunner]

Originally Posted by SGunner

Thanks Joe.

Well I found a service bulletin from alldata.com regarding "Whining from the Front Axle" and I sent it into my dealer. They agree this could be a possible fix but no gaurantee. They have to replace the front Propeller Shaft under warranty this Wednesday.

I'll post the aftermath and hope that this fixes it.

Otherwise I'll keep the carrier bearings in mind. Thanks again!

Ok here you go gang, this is the service bulletin for this problem I believe

Here is the Bulletin...

Whine Noise From Front Axle (Diagnose and Replace Front Propeller Shaft with a Tuned Internally Dampened Front Propeller Shaft) #03-04-17-005 - (03/13/2003)
Whine Noise from Front Axle (Diagnose and Replace Front Propeller Shaft with a Tuned Internally Dampened Front Propeller Shaft)
2002-2003 Cadillac Escalade, Escalade EXT

2000-2003 GMC Yukon Denali, Yukon XL Denali

2001 GMC Sierra C3

2002-2003 GMC Sierra Denali

with AWD Transfer Case (RPO NP3 or NR3)

Condition
Some customers may comment on a slight whine noise from the front of the vehicle during light throttle conditions, typically at two vehicle speed ranges of 64-80 km/h (40-50 mph) and 112-129 km/h (70-80 mph).

Cause
"Inherent" ring and pinion gear whine.

All gear driven units, such as automotive rear axles, produce some level of noise that cannot be eliminated with conventional adjustments and repairs. "Inherent" axle noise can be described as a slight noise heard only at a certain speed on most General Motors® trucks. The presence of this noise is not indicative of a functional concern with the axle assembly. However, some customers may find that this "inherent" axle noise is unacceptable.

Correction
Replace the front propeller shaft with an internally tuned dampened shaft ONLY after diagnosis concludes that it is an "inherent" front axle noise and no physical damage or incorrect adjustment exists.

Diagnostic Information and Procedure for Front Axle Noise
Diagnostic Starting Point - Front Drive Axle (Refer to SI Document ID #696970).
Symptoms - Front Drive Axle (Refer to SI Document ID #696957).
Front Drive Axle Noises (Refer to SI Document ID #700621).
Noisy in Drive (Refer to SI Document ID #700622).
Noisy When Coasting (Refer to SI Document ID #700624).
Intermittent Noise (Refer to SI Document ID #700625).
Constant Noise (Refer to SI Document ID #700631).
Noisy on Turns (Refer to SI Document ID #700634).
Front Propeller Shaft Replacement
Raise the vehicle. Refer to Lifting and Jacking the Vehicle (SI Document ID #737171).

Important
Before disassembly, observe and accurately mark all of the driveline components relative to the propeller shaft and to the axles. These items include the following components:

The propeller shafts
The wheel drive shafts
The pinion flanges
The output shafts
Assemble all of the components in the exact relationship to each other prior to removal. Observe all published specifications and torque values and any measurements obtained prior to disassembly.

Remove the transfer case shield, if equipped.

Remove the clamp (if applicable) (4) at the transfer case (3) by prying up the exposed end of the clamp (4) with a flat-bladed tool.

Remove the bolts (6) and the yoke retainers (7) from the front axle pinion yoke (1).

Notice
When removing the propeller shaft, do not attempt to remove the shaft by pounding on the yoke ears or using a tool between the yoke and the universal joint. If the propeller shaft is removed by using such means, the injection joints may fracture and lead to premature failure of the joint.


Disconnect the propeller shaft (2) from the front axle pinion yoke (1).
Remove the propeller shaft (5) from the transfer case output shaft by sliding the propeller shaft forward.
Inspect the splines of the transfer case output shaft for a sufficient coating of lubricant. If the output shaft does not have a sufficient coating of lubricant, lubricate the shaft with lubricant, P/N 12345879 (Canadian P/N 10953511), or with an equivalent lubricant meeting GM specification 9985830.

Important
Some old driveshaft boots may only use a single clamp design. When installing the new propeller shaft, use ONLY a two clamp boot.


Install the new clamp, P/N 26064275, supplied with the new propeller shaft, P/N 15186002, into the groove of the propeller shaft boot.
Install the propeller shaft splines into the transfer case output shaft.
Install the propeller shaft to the front axle pinion yoke.
Install the yoke retainers and the bolts. Tighten
Tighten the yoke retainer bolts to 25 N·m (19 lb ft).

Install the boot onto the transfer case output shaft until the boot is attached into the groove on the output shaft.

Using the J 43218 , crimp the clamp until the dimensions that are shown are obtained.
Install the transfer case shield, if equipped.
Install the transfer case shield mounting bolts, if equipped. Tighten
Tighten the transfer case shield mounting bolts to 20 N·m (15 lb ft).

Lower the vehicle.
Parts Information
Parts are in limited quantities. DO NOT order parts for stock.

Part Number
Description
Qty

15186002
Propeller Shaft, Front