The Stovebolt Site Forums The Shop Area Driveline Pinion gear binding

Installed new pinion gear and bearings. spins freely. I can se the front edge of the pinion retainer ring through the locking bolt holes. Placed the J-4050 spacer tool in, still no issues. Thread the bolts in to touch, bottom bolt first and still spins. As per Deves, remove the J-4050 tool. begin to put ANY pressure on the retainer bolts and it binds the pinion gear as well as drawing it in so that the J-4050 no longer slips between the rear pinion bearing and the gear. The retainer ring looks to be seated evenly when looking through all 3 bolt holes. Any one have an opinion or experience? First time attempting this, Been at it a few hours and patience has gotten thin. Any help is greatly appreciated.

It sounds like possibly your shims between the housing and the front pinion bearing may not be completely flat and you aren't getting the front bearing seated completely forward. Then as you tighten the retainer bolts, it's compressing the shims more and messing with the space between the rear bearing and pinion. I would pull the pinion back out and recheck the shims.

I concur with Kevin when you tighten the retaining bolts they push the retainer forward as the ends are tapered on the bolts like a pencil.How many shims do you have ? Most of the reading I did found that you have to add to the shims that were already in there.

Don’t know if you seen this one but here is some more info in this article. Hope it helps.

Here is the link to the article that Kevinski found.
[on edit] But i wasn't able to see the whole article.

It appears that you need to click on the button "See All 32 Photos" at top right of the first picture. Each of those pictures has a fairly detailed caption describing what's going on in the particular step in the process, which is the rest of the story, I think.

Thanks for the article, had not seen that one. Unfortunately, I am unable to see the captions associated with the photos. As for my issues. I am 99.9% sure the shims are installed flat. I installed all of the components vertically. I have an extra .10 shim in addition to the original shims per the instructions for a starting point from the Deve's article. Other than that, I'm going to knock it apart today and see if I can figure it out. Anyone else, please chime in. All theories are welcome

I installed my pinion in the standing position. You said the retaining ring was even in all three holes, but is it located properly? I mean, one side of the retaining ring has a taper/bevel. Do you have it in the correct direction where it sits against the three retaining bolts? Just a thought.

One thing comes to mind did you get the big bearing seated all the way .

Thanks. Double and triple checked the orientation of the retaining ring. Torqued the retaining nut. As said, I can see the edge of the retaining ring. The rear pinion bearing is all but dead flush into the torque tube housing. They way I understand it, the retaining ring is wedged forward (away) from the carrier, locking the pinion in place by squeezing the front bearing between the lip of the torque tube housing (and shims) and the pinion retaining bolts. I assume this will cause the pinion to move forward slightly. However, it is drawing the pinion gear flush against the the rear pinion bearing. In the midst of knocking it apart to see what I can find.

Could you get all 3 retainer bolts started with the spacer tool in place .Snug up until no longer moves back then take the tool out .

I am knocking it apart AGAIN today, Having a conversation with Rick who has just finished this job, I failed to compare old and new bearing measurements. That will be the first thing I do. That being said, and ASSUMING the bearings match, I have come to the conclusion that there is not enough shim in the pinion. According to Deve"s directions, add .010 shim to the old shim pack as a start. When I disassembled the rear, I found someone had been in it previously. Most notably there was no gear oil in it, and multiple marks on the retainer ring. Who knows if they assembled it correctly or put correct tolerances back together. Does anyone remember how much shim they used for their finally assembly? I am going to take a swing and probably double the shim pack I currently have installed. My thought process being that the shims are what hold the bearing from bottoming out in the torque tube. The farther rearward the front bearing sits, the farther rearward the pinion gear sits. This should allow the pinion not to bind when the retaining bolts are tightened and allow for the spacing, and removal of the spacing tool. Any shim depth info would be greatly appreciate and save me from another 100x of disassembly.

When I changed mine to 3:55 gears, my two original shims were: .016 and .021. I put the rear end together and thought the pattern was to high on the ring gear. I added a .010 shim, check the pattern and decided to replace the .010 shim with a .005. I was happy with the pattern after that. I'm no expert! This was my first time replacing a ring and pinion. I used multiple instructions from different sites, but feel comfortable I did complete the work correctly - I hope. 🙄

Ed - The 1942-47 Chevy Shop Manual, on Page 4-7 gives the guidelines for shims when reinstalling the original ring and pinion or replacing the ring and pinion gears. Below is a snapshot from the book with the details. Hope it's of some help.

Here is some imfo from the book from Jim carter