The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   All 4x4 Tech & Off Roading (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=30)
-   -   1994 Burb 4 x 4 Transfer Case Question (https://67-72chevytrucks.com/vboard/showthread.php?t=516170)

Already Gone 03-25-2012 01:09 AM

1994 Burb 4 x 4 Transfer Case Question
 
On my 1994 bone stock never touched 4 x 4 1500 Burb with the transfer case on the floor when you have the lever in 2 high is anything turning in the front axle? I just came back form a 1300 mile round trip ( and was in 2 high all the way) pulling a trailer and now I have a little whine from the front of the Burb. Anyone have any idea what it could be?

snj8198 03-25-2012 09:51 AM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
Hi, First it's necessary to find if the noise is from the motor and accessory drive system or from the drivetrain. Does the wine exist when the motor is running but in park? or only when you are driving?

Have you noticed any vibrations or wobbles, or change in the whining sound in terms of volume and/or pitch when driving, turning, or braking? Maybe you can get someone to drive the vehicle in a large parking lot or open area while you walk along side to listen for the noise.

Some possible things to look for:

Your front axle assembly and front driveshaft does turn when driving even in 2 wheel drive since your vehicle is not equipped with lock out hubs. This continual spin tends to wear out the u-joints in the front shaft. Check them. I have found that even if they may not necessarily be loose when you wiggle them the needle bearings start breaking up in large enough chunks that keeps the joint firm for a while but emits a squeek when driving. The joint only becomes loose when the needle bearings are finally ground to dust allowing the slack to be witnessed. They wear out faster than a guy thinks they should being a front drive application. But since they do spin all the time and they are usually non-serviceable (no grease zerk) they do conk out.

Another possibility could be a front unit bearing. Have you noticed any adverse handling or feed back in the steering wheel? Walk along side and listen to each side as someone drives in a parking lot or so. A guy could jack up each side and try wiggling the tire side to side. If you find any play then it's time to replace the unit bearing which may or may not squeek (I've seen them do both during failure). If you find excessive movement when wiggling the tire up and down you need a ball joint or two but this would be a different find and should not contribute to your whine. Just a quick and easy check item while the tire is off the ground.

Again it's important to narrow it to a drivetrain noise and be sure it's not an accessory drive noise. If it is from the the accessory system check the tensioner pully as they conk out anytime without warning. Check the power steering pump. Additional weight and load on an aging pump can push them over the edge, I have found them to whine in the past when they are about to give out.

I think that's all I can think of now. I'll roll it around over another cup of coffee. Good luck sir.

-steve

mknittle 03-25-2012 10:28 AM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
:agree::agree

Already Gone 03-25-2012 04:45 PM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
Quote:

Originally Posted by snj8198 (Post 5273504)
Hi, First it's necessary to find if the noise is from the motor and accessory drive system or from the drivetrain. Does the wine exist when the motor is running but in park? or only when you are driving?

Have you noticed any vibrations or wobbles, or change in the whining sound in terms of volume and/or pitch when driving, turning, or braking? Maybe you can get someone to drive the vehicle in a large parking lot or open area while you walk along side to listen for the noise.


Some possible things to look for:

Your front axle assembly and front driveshaft does turn when driving even in 2 wheel drive since your vehicle is not equipped with lock out hubs. This continual spin tends to wear out the u-joints in the front shaft. Check them. I have found that even if they may not necessarily be loose when you wiggle them the needle bearings start breaking up in large enough chunks that keeps the joint firm for a while but emits a squeek when driving. The joint only becomes loose when the needle bearings are finally ground to dust allowing the slack to be witnessed. They wear out faster than a guy thinks they should being a front drive application. But since they do spin all the time and they are usually non-serviceable (no grease zerk) they do conk out.

Another possibility could be a front unit bearing. Have you noticed any adverse handling or feed back in the steering wheel? Walk along side and listen to each side as someone drives in a parking lot or so. A guy could jack up each side and try wiggling the tire side to side. If you find any play then it's time to replace the unit bearing which may or may not squeek (I've seen them do both during failure). If you find excessive movement when wiggling the tire up and down you need a ball joint or two but this would be a different find and should not contribute to your whine. Just a quick and easy check item while the tire is off the ground.

Again it's important to narrow it to a drivetrain noise and be sure it's not an accessory drive noise. If it is from the the accessory system check the tensioner pully as they conk out anytime without warning. Check the power steering pump. Additional weight and load on an aging pump can push them over the edge, I have found them to whine in the past when they are about to give out.

I think that's all I can think of now. I'll roll it around over another cup of coffee. Good luck sir.

-steve

Thanks for your help Steve. The whine is only there when I am driving and the steerng is tight with no wobbles etc. The whine increases as I accelerate. I am hoping its a u-joint or wheel bearing as opposed to the front differential. The Burb was a well looked after one owner before me and only had 138,000 miles on it when I bought it and now has 144,000 miles and from what what I've seen of Burbs, with this mileage its just broken in.

snj8198 03-26-2012 11:47 AM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
Ya sounds like it very well could be either a bearing or u-joint. Is it louder on one side of the vehicle? Sometimes a u-joint's death squeal will go away at higher speeds. Does yours do this? It may be time to get dirty.

Already Gone 03-26-2012 01:07 PM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
Quote:

Originally Posted by snj8198 (Post 5275854)
Ya sounds like it very well could be either a bearing or u-joint. Is it louder on one side of the vehicle? Sometimes a u-joint's death squeal will go away at higher speeds. Does yours do this? It may be time to get dirty.

Yes it seems to be louder on the pass side as and as far as getting dirty, I leave that kind of work to the pros and am happy to write a check for it.

snj8198 03-26-2012 01:16 PM

Re: 1994 Burb 4 x 4 Transfer Case Question
 
;) good luck sir!


All times are GMT -4. The time now is 06:42 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2026, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com