Do you hear a whirring noise when in 4x4? Please post.

[BlazerLT]

What I mean is when you are travelling at 30mph or higher do you hear a slight faint whirring noise at all?

The thing is, I used to never hear it but that was when the tranny to transfer case seal was leaking and the transfer case was really overfilled.

Now that it is at the proper level I can hear the 4x4 whir a bit when it is engaged. When I have a laod on it I hear it, when I let off the gas it goes away.

Noise is the loudest at 30mph and get quieter if you are slower or if you are faster.

Let me know you thoughts guys.

[ZL1power69]

i don't remember hearing any noise like that while in 4x4

[MT-2500]

Originally Posted by BlazerLT

What I mean is when you are travelling at 30mph or higher do you hear a slight faint whirring noise at all?

The thing is, I used to never hear it but that was when the tranny to transfer case seal was leaking and the transfer case was really overfilled.

Now that it is at the proper level I can hear the 4x4 whir a bit when it is engaged.

Noise is the loudest at 30mph and get quieter if you are slower or if you are faster.

Let me know you thoughts guys.

BlazerLT
This noise may be ring gear and pinion or rear end bearings.
{{When I have a laod on it I hear it, when I let off the gas it goes away.}}
Did they get the preload set right when they changed pinion seals?
Here is a link with some good info on preload and rear ends.
http://www.differentials.com/install.html
http://www.differentials.com/diagnose.html
Good Luck MT

[BlazerLT]

Originally Posted by MT-2500

BlazerLT
This noise may be ring gear and pinion or rear end bearings.
{{When I have a laod on it I hear it, when I let off the gas it goes away.}}
Did they get the preload set right when they changed pinion seals?
Here is a link with some good info on preload and rear ends.
http://www.differentials.com/install.html
http://www.differentials.com/diagnose.html
Good Luck MT

It is only in the front differential and by the sounds of it it is getting better as I drive it more and more. The noise was there before the pinion seal was changed yesterday.

Seeing the 4x4 is not used very much it might just need the new fluid circulating for a bit to get it where it should be.

The noise isn't really loud at all, just a light whirring noise.

The dealership said some noise is normal.

The one thing is that it could be coming from the transfer case and seeing it was overfilled for the timeframe which I owned the truck seeing the tranny-transfer case seal was leaking, maybe it is the normal sound?

[BlazerLT]

What is a carrier bearing? Anyone got any pics of what it is? I am wondering if that is what it is.

I also for a while have been feeling a weird faint rumbling in the front that will fade every time I go over a crest of a bump in the highway at highway speeds. You know those loping hill in the road or over the crest of a hill at slower speeds.

Also, is ther any additive I should be adding to the gear oil? It is GL-5 75w90 synthetic I am using.

[DetroitMuscle]

Originally Posted by BlazerLT

What is a carrier bearing? Anyone got any pics of what it is? I am wondering if that is what it is.

I also for a while have been feeling a weird faint rumbling in the front that will fade every time I go over a crest of a bump in the highway at highway speeds. You know those loping hill in the road or over the crest of a hill at slower speeds.

Also, is ther any additive I should be adding to the gear oil? It is GL-5 75w90 synthetic I am using.

Is it "limited slip"? If not then you do not need to add anything. Only time a diff should get an addative is when its a limited slip unit and has a tag on the gear cover stating it needs the addative.

If you are running aftermarket synthetic I do believe the lube has the limited slip addative already in it.


Why synthetic might I ask?


A carrier bearing is inside that first thing you see when you pop the diff cover off, the axles slide into the carrier and the carrier is attached to the ring gear which goes to the pinion, ect ect.

Carrier bearings do go out But all my expierences with them is its usually the carrier spider gears that go first then the bearing.

[BlazerLT]

I am using MotorMaster Synthetic 75w90. Stuff looks like orange coolaid.

It was weird, when the weather was cooler, you couldn't hear the noise anymore. I wonder if the synthetic is a little too thin seeing it calls for 80w90 conventional.

Also, it isn't a limited slip.