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Advise on diagnosing front inner bearing replacement.

4260 Views 11 Replies 3 Participants Last post by  steveO
I would like to confirm that the inner bearing on the driver side needs to be replaced.

When I Grab the end of the CV going into it, there is up and down play.
Don't know how much if any is normal or if there should be any play at all.

The hub on this side was recently replaced, reducing the noise.
The other side was replaced last year.

The CV joint is OK, it doesn't knock or leak grease, I don't believe this type of noise is related to the CV correct?

If I drive slowly in a parking lot and put stress on the driver side (hard turn right), I don't feel any vibration. When I bring it up to 40 mph or above I can feel and hear a groan and feel a vibration in the wheel when I turn to the right.

Is this common?
How difficult and costly is it to do DIY
What all should be replaced while its apart assuming it the bearing.
Is it about to self destruct on me?

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Is the play at the differential or the hub? We don't have the older inner/outer bearing setup. Our wheel bearings are within the hub.

You parking lot circle test sounds like it's the driver side hub going bad again.
Both hubs were replaced. The driver side was just replaced a month or two ago.

I also had to replace the seal on the driver side, it was leaking.

Play is at the point where the CV spline assembly goes into the seal the bearing at the front differential I can push it up and it moves.

I put it in 4WD and drove it and it didn't seem to make any unusual noises.
I didn't do the stress test with it in 4WD

I was just doing maintenance on my wifes CRV and the CV joints don't move at all but thats front wheel drive.
can't find a spec for the diff bearing but any play in a bearing is bad. I would say 1/32" movement is too much but thats just me.

What you can do (time and $$ involved) is remove driver cv axle, drain diff fluid and seal of the cv axle hole and drive it around. Gatorade caps block them off good
Just compared the two sides and the drivers side is moves a lot compared to the passenger side.

Say it is bad ... any idea how hard to do replace and how much it costs ?
The front diff has to come out and opened up. Oil pan comes out too. Then you might discover the other bearing to be bad. If you take it to a shop it will probably be easier to buy a used low mileage front diff.
I thought the diff has to come out to change the bearing on the oil pan side. The bearing where the driver's side CV shaft fits into can be changed from the outside just like the CV shaft seal. You just need a good quality slide hammer kind of bearing puller to extract the old one. I can't find it at the moment, but it's been documented here on trailvoy.
I'll take a look for that post.

Thats good news because I looked at the drawing I found on this board for the differential and was wondering how I was going to to remove half the cover..

I have a homemade slide hammer adapted from a large dent puller for seals.
I will have to make an attachment to use it to pull a bearing.

A slotted piece of strong steel should do it.

What function does the adjuster serve before the bearing?
Any suggestions on an after-market bearing?
According to this pic there are 2 bearings on each side. One on the diff (#25) and one in the case for CV support (#36). I would think they would both have to be bad for the CV to move alot. With the CV engaged in the spider gear it shouldn't move unless their is play in the diff bearings.

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I'd appreciate if anyone who has an explored view of the drivers side could post it.
I looked, can't seem to find the drivers side and the parts site had the wrong one.


Thanks LMMJ ! Looks like you beat me to it!
#25 and 20 are the carriers. I think if I had a constant noise they could be at fault.
I don't have any unusual noises when its in 4WD.

Considering the noise only shows up when I stress the drivers side, I'm thinking the torque or thrust being placed on the input side of the CV shaft is stressing the bearing that the CV shaft rides on.

#36 is the bearing, I guess, #37 is the adjuster ( whatever that is doing I have no clue) and #38 is the seal (I recently replaced already)

So it looks like 36-38 get replaced.
If the carriers go I'd probably try to get a junker... hopefully thats for another day.

I'll probably replace the CV this time as well even though it is not making noise.
so that the new bearing has a new surface and most likely a better fit.
Part number assistance

Does anyone have the GM numbers for #36 and 37?

The seal is 12471618

I would like to confirm these because I'm ordering these online and had issues with getting the incorrect parts on the differential unit in the past.

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