Pinion Bearing Questions

[TC4x4]

So i took the truck to the shop and they said that they can change it out for 700$ and it will take more that one day. That seems kind of unrealistic to me but maybe I am wrong bec I am not familier with the internals of a differential, but I want to learn about whats in there so i can be to a point where I can work on it myself, it is a 1993 chevy 10 bolt in a full size blazer, the one in my avatar.

Now my question is this, how do i change out the pinion bearing. Is it a really hard thing to do and will I be able to do it on my own. What will go into doing this? I can't afford the shop bill and I really want to learn more and what a better way that going in there and doing it yourslef, so could someone walk me throught this? Thanks guys

 

[BILTIT]

Yes you can do it yourself, just takes some research the right tools and some time/patience. First off, are you sure its the pinion bearing?

 

[TC4x4]

That is what the shop said it was as soon as they test drove it. What tools will i need and how do i change it out?

 

[Hogback Fabrication]

First make sure that it is the pinion bearings. If the bearings are bad there will be some side to side or in and out play at the yoke (a little rotational is ok).



If the ring and pinion are still okay, you will only need a ~$80 install kit (replaces all the diff bearings and the pinion seal).

Here is an article showing how to setup gears. Unless you have someone helping you that has done them before it will be a very long and tedious process for you.

To do it the right way you will need a dial indicator with some kind of base (to check backlash), a dial torque wrench that reads in in. lbs. and set of calipers to measure shims.

If you are only replacing the pinion bearings you could probably get away with just the torque wrench.

If you do decide to undertake this project there are a few of us on here that know how to setup gears and can help you.

 

[Hogback Fabrication]

To summarize replacement of only the pinion bearings:



Take off the diff cover

Put the rear end on jack stands and remove the tires

Remove the c-clips from the differential carrier

Remove the axle shafts

Mark the bearing caps so they get reinstalled EXACTLY as they were and remove them

Remove the carrier. There are shims on each side of the carrier and you will have to reinstall these exactly as they were. If you mess that part up you will have to buy more tools and make a lot more work for yourself.

Remove the rear driveshaft

Remove the pinion nut and yoke

Use a punch in the cup of the pinion (i.e. don't hammer on the threads) and hit the pinion through the housing

Use a press to get the lower pinion bearing off of the pinion. There is a shim underneath the lower pinion bearing, save this because it will need to be reinstalled in the same place.

With the shims under the bearing, press the new lower pinion bearing onto the pinion

Remove and replace the outer races from the housing (using a punch)

Reinstall the pinion into the housing with the new crush sleeve, pinion seal and upper pinion bearing.

Tighten the (new) pinion nut down until you have the correct pinion bearing preload (usually 15-25 in.lbs.)

Reassemble everything else and you should be there.

 

[obijuan]

didnt you ask this earlier? did anyone mention to you getting a new rear axle? try the 14 bolt semi float in the 6 lug fashion. they come on the light duty 3/4 tons or something of your era trucks. you could probably score one with way better gear ratio and a good pinion bearing for way cheaper. it would probably go right in with little adjustment.


and if youd like to fix a ten bolt, go pull a different one from a JY. still less expensive and you get familiar with your truck. OR if you wanna try it, you can do it yourself. that guy youre paying is doing it himself and had the first one at one point. just pay attention to the details.

 

[Hogback Fabrication]

Even if he gets a rear axle with different gears he will have to have the front re-geared which is even more $$$


BTW, $700 is WAY too much for bearings in a diff. I generally charge $150 labor for a diff that's in the truck and that requires setting up different ratio gears which is a lot more work than just rebuilding a rear end. I could probably remove and replace all the bearings in a 10 bolt in a few hours.