Base91

iTrader: (1)

I'm partially rebuilding a diff for the first time. It's a 9-bolt. I've had the carrier and cones machined, it's shimmed and back together with nearly 1/8th of an inch in front of the cones. I'm looking at the pinion and intend to use a solid spacer in place of the crush sleeve. My question is on setting the pinion depth. Am I correct that the bearing needs to be pulled off the pinion shaft and any needed shims added before it's re-installed? And if that's required the shimming of the spacer would need to be re-adjusted too? BTW it's a 3.27 diff not the original 2.77.

trafficlightguy

Yes, press. Your old bearing off buy a new pinion bearing,

Take you old bearing and hind the inside diameter a little until it slides on the pinion shaft
Use that to adjust the gear set, one you have it perfect then press your new bearing on

You will be removing it a few tine to get the right gear set, it took me about 3 hours to get it perfect, but I'm analretentive.

Twin_Turbo

iTrader: (25)

The inside is best clearanced with a flapper wheel on a die grinder, with a hone it takes forever

Base91

iTrader: (1)

Great. Thanks for the info.

big gear head

Don't install the spacer until you have the pinion depth set. Then you can shim the spacer for the correct pinion bearing preload and then do your final assembly. Each time you do a trial assembly to check the contact pattern be sure that you set the pinion bearing preload correctly. Use your old pinion nut for this and just tighten the nut until you have the preload right.

There are shims that you can use behind the inner pinion bearing race to set the pinion depth. Using these shims requires driving the race out of the housing each time you change shims. Many of tghe Dana rear ends are set up this way. I would rather press the bearing off and on that do it this way, but if you don't have a press this might work for you.

I'm assuming that you are using all new bearings for this. When you drive the old inner pinion bearing race out of the housing you might find shims in there. I can't remember how the factory shimmed the 9 bolt, if it was behind the bearing or the race.

Base91

iTrader: (1)

So when just test fitting for depth I don't need the spacer or crush sleeve? Just made sure the pre-load is correct?

big gear head

Correct. Just use the spacer for the final assembly.

Base91

iTrader: (1)

Thanks again.

Base91

iTrader: (1)

I tried to install the pinion and diff but couldn't get it in correctly. I discovered the pinion bearings are different. The one that came out has 17 rollers but the "new" one has 18 rollers that are slightly longer and the bearing diameter is larger. For now I'm going to use the original smaller bearing but is the normal set up? The original was a 2.77 and I'm installing a 3.27. On the Ratech site I only see one part number for the pinion bearing.

SLEEPER 86

Did you get a new bearing race with your bearing? If so, the bearing and race will work together and not be a problem. Is it the inner or outer pinion bearing?
Auto Zone sells the races separately.

SLEEPER 86

While we're on this topic I have a few questions. The old outer pinion bearing I have looks kind of rough, I have a spare new one also. Would it make a difference which one I hog out for a slip fit and use for setup?
Also, my pinion had a. 025 shim under the race and none behind the bearing. I got a set of the severe duty shims from Ratech, but it seems the closest I can get is. 027. Would that be an acceptable starting point? It seems the shims get damaged when pounding the race out, so I'd like to do this as few times as possible.
Lastly, is it ok to lightly clean up the housing and caps where the carrier races ride with some 4/0 steel wool or a green scitchbrite pad or is this even necessary?

big gear head

You can shim the 9 bolt behind the bearing just like the 10 bolt if you have the right shims. You don't have to shim it behind the race.