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Instructions for crush sleeve elimination kit

How about this. Put a piece of threaded rod through the bearings instead of the pinion, and put a shim pack between the bearings so that when you tighten the nuts on the threaded rod, you have some preload on the bearings. Then slack off one nut one inch, and tighten the other nut. That threaded rod has moved one inch inside the bearings. Has the preload changed?
Pinion Depth: Where Do I Start.....
 
Here's a visual. If you add a shim under the large bearing, you shorten the distance to the shoulder at the small bearing. Subtract a shim under the large bearing you lengthen the distance to the shoulder. The shoulder is where the preload shim sits under the small bearing. Changing this distance changes the preload.
Screenshot_20221202-221357_Gallery.jpg
 
Stop giving me information on rearends that adjust pinion depth by shimming the rear bearing cup out of the case, and read what I said. Rear ends like the 8 3/4 adjust the depth by shimming the pinion out from the rear bearing and therefore has no affect on preload When putting a gear set in a housing you start with the pinion depth first and then set the preload, I get that. If when it is all assembled, you determine the pinion depth needs adjustment, you can take it all apart and change the pinion shim, and put it back together without changing the pre load. One the type of rear end you keep talking about, you have to change the preload shims the same amount as the cup shims, only opposite.
 
Yes,a brain fart on the 742 pinion. What I said is true on 741 and 489 with the crush sleeve eliminator, as the preload sleeve presses on the bearing itself.
 
Glad I wasn’t missing out on something simple. After studying my parts awhile I still tend to agree with R/T Boy 67. It looks like changing the pinion depth just slides the pinion in or out of a fixed column of parts - inner bearing race, spacer, spacer shims, outer bearing race, yoke and yoke washer. The bearing cup installations are a fixed distance apart in the housing so no matter where the pinion is moved in or out, the bearing races have to remain the same distance apart. If the preload shims are changed you change the distance between the bearing races. I guess in a few weeks I’ll figure it out one way or the other by trial and error.

Now if I can just figure out how tightening the pinion nut to a point just pulls the column of parts together and sets the preload, but further torquing after that does nothing more than tension the pinion without jamming up the bearing races into the cups.:rolleyes:
 
Stop giving me information on rearends that adjust pinion depth by shimming the rear bearing cup out of the case, and read what I said. Rear ends like the 8 3/4 adjust the depth by shimming the pinion out from the rear bearing and therefore has no affect on preload When putting a gear set in a housing you start with the pinion depth first and then set the preload, I get that. If when it is all assembled, you determine the pinion depth needs adjustment, you can take it all apart and change the pinion shim, and put it back together without changing the pre load. One the type of rear end you keep talking about, you have to change the preload shims the same amount as the cup shims, only opposite.
Wrong, Wrong, Wrong. Any time the pinion depth is changed the preload changes with it. The 8 3/4 is the same as any other differential.
 
Maybe this we’ll help visualization with this subject. Ignore pinion depth shims mangled appearance - it happens. Remember - the bearing cups distance apart in the housing is fixed.

8E6F28A6-22A3-449C-A688-33745816B184.jpeg
 
Maybe this we’ll help visualization with this subject. Ignore pinion depth shims mangled appearance - it happens. Remember - the bearing cups distance apart in the housing is fixed.

View attachment 1381931
The front bearing is fixed and doesn't move with the pinion....so if you need to move the pinion say .005 deeper, what happens to the preload?
 
Maybe this we’ll help visualization with this subject. Ignore pinion depth shims mangled appearance - it happens. Remember - the bearing cups distance apart in the housing is fixed.

View attachment 1381931
When the pinion depth is changed the pinion stem now moves between the bearings. The front bearing race is fixed. The shims need to be adjusted to properly load the pinion. The step circled is moving in or out depending on the pinion shim. This step is locating the bearing and needs to be adjusted.

pinionp.jpg
 
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When the pinion depth is changed the pinion stem now moves between the bearings. The front bearing is fixed. The shims need to be adjusted to properly load the pinion. The step circled is moving in or out depending on the pinion shim. This step is locating the bearing and needs to be adjusted.

View attachment 1381948
The front bearing race locates the front bearing cone....not the step or shoulder....
 
Maybe this we’ll help visualization with this subject. Ignore pinion depth shims mangled appearance - it happens. Remember - the bearing cups distance apart in the housing is fixed.

View attachment 1381931

You'll find out how it works when you go to set it up unless you hit it perfect on the first try. Doubt that will happen but you never know. Good luck! I mean that sincerely.
 
The front bearing race locates the front bearing cone....not the step or shoulder....
The step or shoulder shims will move the bearing on the pinion stem. The race is fixed into the case.
 
You'll find out how it works when you go to set it up unless you hit it perfect on the first try. Doubt that will happen but you never know. Good luck! I mean that sincerely.
I've never done that. Got close a couple of times though....then there were the ones that fought ya tooth and nail lol
 
The step or shoulder shims will move the bearing on the pinion stem. The race is fixed into the case.
Right...too many shims and the bearing will be loose in the race....not enough will make it tight. Kinda like a front wheel spindle bearing set up. Same principle but no shims. Just snug the nut, back it off a hair and put the keeper lock on it. Sure would be nice to be able to set up a rear end like that! lol
 
If the outer bearing truly did bottom out on that machining step on the stem, the spacer would be rendered completely useless.
Nothing bottoms out on that step. 8 3/4 or otherwise. Think of it in terms of the crush sleeve instead. No shims, no bottoming out.
 
The original post was about an 8 3/4 rear end. The pinion depth is adjusted by the shim between the pinion head and the bearing, not between the cup and the housing.

I've seen many original 489's with a .032" shim under the rear bearing cup.
 
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