Possible Bad Wheel Bearing

[FarmerSid]

Wanted to ask here before I start throwing parts at my truck. I have a '04 Sierra 2500 LD crew with a 6.0 in her. I have been reading here and nothing specific for my symptoms. This just started the other day. When in 4X4 and I let off the gas I hear a whine/howl type sound that seems to be coming from the passenger side. If I accelerate it mostly goes away. The 4X4 works fine. I can tell when it is in and out of 4X4. It goes in and out of 4X4 as it always did. I have autotrac. The indicator lights flash a few times then go solid as it should. I get no dumbie lights going off in the dash whatsoever. Everything seems fine.

 

I call the dealer (Canada) and price out a new bearing ($401) and after I describe whats going on, he says that I should bring it in and get it scanned as it could be a couple other parts causing the problem. One is, what he called, a transfercase module up behind the dash at a price of $597.25 or the selector switch (buttons you press to engage/disengage 4X4) to the left of the steering wheel at a price of $144.75. This scan job would be a min of 1 hr shop time at $89/hr.

 

What do you all think is going on here? Want to try and figure out what's going on so I don't start throwing parts at it.

 

Cheers!

 

Sid

 

I priced the bearing at a local Parts Source (fellow Canadians will know this store) and they want $423.75 for a SFK unit. Almost $25 more than the dealer. LOL!

[Draenor]

I would believe its the differential.

[Draenor]

*double post*

[FarmerSid]

I would believe its the differential.

 

Care to explain more about this?

[Draenor]

You state that you only get the whine or howl that usually goes away on acceleration. That usually occurs if differential gears are not mashing up correctly. A whirring sound would tend to come from wheel bearings.

 

Its hard to tell not being able to hear the actual noise.

[FarmerSid]

You state that you only get the whine or howl that usually goes away on acceleration. That usually occurs if differential gears are not mashing up correctly. A whirring sound would tend to come from wheel bearings.

 

Its hard to tell not being able to hear the actual noise.

 

Thanks for the reply! OK, what would be causing the gears to not mesh up correctly? What may have failed to cause this? Would bad bearing sounds be amplified when in 4X4?

[J-man67]

I also agree...it may be the differential. Your backlash on your gear may not be correct causing the gear and pinion to whine.

[FarmerSid]

I also agree...it may be the differential. Your backlash on your gear may not be correct causing the gear and pinion to whine.

 

What would cause this to happen? I hardly use 4X4 and have never been off road with it or horsed it in the 1.5 yrs I owned it. Snow is starting to fly and want to get this fixed before too long. I tried 4X4 briefly on my way home from work and everything works fine. 4X4 low, high, auto. You can hear it clunk going into gear going into 4 low more than the others but it goes in fine and dives in all modes fine. Just a low pitch howl when letting off the gas. I heard it too tonight when pulling up to the shop when turning somewhat sharp in low 4. Truck drives straight on the highway (2 high) and does not pull at all when braking soft or hard.

[zaac]

You state that you only get the whine or howl that usually goes away on acceleration. That usually occurs if differential gears are not mashing up correctly. A whirring sound would tend to come from wheel bearings.

 

Its hard to tell not being able to hear the actual noise.

 

Thanks for the reply! OK, what would be causing the gears to not mesh up correctly? What may have failed to cause this? Would bad bearing sounds be amplified when in 4X4?

 

I believe worn bearings could change the backlash. As for wheel bearings, I replaced one of mine about 6 months ago. It would get noticeably louder if I cranked the steering wheel while driving to put more weight on it. Very easy to detect.

[FarmerSid]

You state that you only get the whine or howl that usually goes away on acceleration. That usually occurs if differential gears are not mashing up correctly. A whirring sound would tend to come from wheel bearings.

 

Its hard to tell not being able to hear the actual noise.

 

Thanks for the reply! OK, what would be causing the gears to not mesh up correctly? What may have failed to cause this? Would bad bearing sounds be amplified when in 4X4?

 

I believe worn bearings could change the backlash. As for wheel bearings, I replaced one of mine about 6 months ago. It would get noticeably louder if I cranked the steering wheel while driving to put more weight on it. Very easy to detect.

 

 

zacc,

 

Did this happen in both 4 and 2 wheel drive? My issue only happens in 4X4.

[J-man67]

If it was a wheel bearing, it would be detectable in any mode. Also, try to limit turning on dry pavement when in 4wd. You can really bind it up.

[zaac]

zacc,

 

Did this happen in both 4 and 2 wheel drive? My issue only happens in 4X4.

 

I was in 2wd, never tried it in 4wd. If it only happens to you in 4wd I sure don't think it would be a wheel bearing. Maybe if you jack up the front end and take off the driveshaft and turn the front diff by hand you will be able to feel some binding or roughness. I dunno. Wish I could help more.

[Draenor]

If it only happens to you in 4wd I sure don't think it would be a wheel bearing.

The wheel bearing would be constant.

[FarmerSid]

I understand that a bad bearing would be showing signs of going out regardless of being in 4 or 2 wheel drive. Maybe the sounds the bad bearing are making are amplified when in 4X4? Don't know.

[zaac]

I understand that a bad bearing would be showing signs of going out regardless of being in 4 or 2 wheel drive. Maybe the sounds the bad bearing are making are amplified when in 4X4? Don't know.

When my wheel bearing went out I jacked up both front wheels and compared. On the bad wheel I could easily rock the tire when pulling on the top and bottom of the tire. The good wheel had no play. Could also hear/feel the bad one when I spun the tire.