How tight are NEW diff bearings supposed to be???

[77K10Silverado]

I've replaced the diff bearings on my front 10 bolt and boy is super tight going back in. I'm using the same factory shims and have double checked that the bearings are pressed as far on as possible. How tight is this thing supposed to be? I have to hammer it in hard with the dead blow and when in, I have to use both hands to spin the thing. No pinion in yet as I wanted to test fit.

Thoughts or how tight this supposed to be and suggestions?

Thx folks!!!

[kalbert]

Setting up an axle is a little bit science and a little bit art, and it's not for the faint of heart. Usually putting new bearings in with factory shims will get you close, but you'll want to check the mesh pattern and backlash to dial it in.

http://www.fourwheeler.com/how-to/tr...y-jeep-willys/

[trixter99]

Given the fact that you changed the bearings and the bearings hold the carrier in the housing I would say you need to re shim align the whole thing.

[indymachinist]

Agree with the above. It is not so simple as slapping new bearings on and putting it back together.

[77K10Silverado]

Originally Posted by trixter99

Given the fact that you changed the bearings and the bearings hold the carrier in the housing I would say you need to re shim align the whole thing.

If that's the case, then why doesn't every kit come with shims?

[Jake Wade]

If all you did was change the carrier bearings, a shim change is not needed, hopefully you used Timkens.

[Jake Wade]

It is however very important that you put back the same shim(s) back in the side they came from

[trixter99]

He just said there was no pinion in the diff yet and that it is hard to turn. My years of experience tell me that the bearing tolerances are a little off and that he does in fact need to have the diff re aligned and shimmed properly or you run the risk of bearing failure and or premature gear wear and noise. This is my opinion based on trying to do this exact project while trying to save a few bucks, only to end up disappointed.

[jjzepplin]

Yeah something does not sound right. My hammers are the most unused tools I have. I usually pull them out when working with concrete or busting up some block.
Small taps maybe but really banging it in there no.

[77K10Silverado]

Originally Posted by Jake Wade

It is however very important that you put back the same shim(s) back in the side they came from

Oh yeah I def tagged and bagged when removed.

[77K10Silverado]

Originally Posted by trixter99

He just said there was no pinion in the diff yet and that it is hard to turn. My years of experience tell me that the bearing tolerances are a little off and that he does in fact need to have the diff re aligned and shimmed properly or you run the risk of bearing failure and or premature gear wear and noise. This is my opinion based on trying to do this exact project while trying to save a few bucks, only to end up disappointed.

I did the rear last winter and I could put the diff in and out with a small amount of force. It also was able to be spun with one hand freely. This is just way too tight, I think your right.

[ElGracho]

Proper preload on your carrier bearings will make it unlikely that you will put the carrier in by hand. Light tapping should be expected on the bearings/shims as you install the carrier. I usually put the carrier, bearings and one side shim in and then tap in the other side shim (or shims when building up a new ring and pinion installation).

Once the carrier is in and the shims are seated, it should turn by hand easily. Needing two hands means either too much preload or something is cocked in the rear end housing.

This page has tons of good info no matter whose parts you use:

http://www.ringpinion.com/Downloads/Installations.aspx

Read the "Yukon Installation Kit Instructions" especially.

[Jake Wade]

Why do you have the pinion out? If this is a different carrier, or a different gear set then yes, a re shim will most likely be necessary.

Something is not right if you cannot spin it or, hard to spin. You don't want the carrier to fall in but, you don't want to beat it in either.

My point is, IF a differential it set up correct and all that is being done is carrier bearing replacement, Re shimming is not the norm.

[77K10Silverado]

Originally Posted by Jake Wade

Why do you have the pinion out? If this is a different carrier, or a different gear set then yes, a re shim will most likely be necessary.

Something is not right if you cannot spin it or, hard to spin. You don't want the carrier to fall in but, you don't want to beat it in either.

My point is, IF a differential it set up correct and all that is being done is carrier bearing replacement, Re shimming is not the norm.

I'm doing a complete front end rebuild. Only new bearings and races.
Go to my build to see pics.

I'm going to put a vid up tomorrow morning to show the resistance.

[v30crewcab]

make sure you got the correct races. they have several different races that fit the same bearing, and they are different thickness.
the correct way to do it is to spread the diff open with a diff spreader, and measure it to 15 thousands. they should be tight, but should be turnable. how do you have that in without the pinion? just doing a check? kinda hard to get the pinion in afterwards!

[v30crewcab]

also, you do have the main caps in correct, not upside down, or swapped side to side? they are machined for a specific spot.

[77K10Silverado]

Originally Posted by v30crewcab

make sure you got the correct races. they have several different races that fit the same bearing, and they are different thickness.
the correct way to do it is to spread the diff open with a diff spreader, and measure it to 15 thousands. they should be tight, but should be turnable. how do you have that in without the pinion? just doing a check? kinda hard to get the pinion in afterwards!

Yes test fit. I've knocked it in and out a few times checking things. I also used my mic to measure and the races are only like .05-.02 different from the factory races. Hell I've swapped in the factory ones to see and is still the same.

Thoughts.... The kit says its for a 10 bolt and I think Dana 44. Could there be a difference? I'm going to check the box and provide p/n's in the am as well.

[77K10Silverado]

Originally Posted by v30crewcab

also, you do have the main caps in correct, not upside down, or swapped side to side? they are machined for a specific spot.

Never even put them in. It's tight as fug without them even in yet.

[Jake Wade]

Were the mounting surfaces on the carrier for the bearings clean and flat? It only takes thousandths to throw things off.

[77K10Silverado]

Originally Posted by Jake Wade

Were the mounting surfaces on the carrier for the bearings clean and flat? It only takes thousandths to throw things off.

Def something to look at.

Thx for all the suggestions friends.

[77K10Silverado]

Here is the exact kit I bought. Says its for...Front/Rear; Standard Kit; GMC; 8.5" R.G.

http://shop.advanceautoparts.com/p/n...9-P#fragment-2

[mrolds88]

Since you have a different measurement from old to new (.05 - .02) you will need to do at least 1 of 2 things. First is to make sure your inner bearings are fully seated. If they are then you will have to remove some shims. .020 is a lot in this situation. .050 is a lot more. That is almost a 1/16". Get a bit of gear marker to double check your pattern then.

[lowridergmc]

make sure your side bearings are pressed all the way on your carrier.when i do them i put the shims in one side and find on the other side the shim will usually fit in 1/2 way by hand and i tap it the rest of the way.