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Discussion Starter #1
I am installing a new set of FMS gears. The rearend does not have the stock gears, so I will need to find the proper pinion depth. If I understand correctly, I am supposed to install the pinion bearing and then put the pinion into the housing to determine pinion depth and the number of shims to use.

Once I determine the amount of shims needed, what are the backyard mechanic ways to remove the bearing so that it can be installed a second time?

Thanks,
 

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I believe if you don't have an existing ford gear and you don't know the new gear's pinion depth you are supposed to start with 0.030. The best way to go is to buy a second pinion bearing and grind out or use a drum sander to open it up so that you can slip it on and off without too much effort. Google search for "pinion setup bearing". You'll see people using flapper sanding wheels an other grinding methods. Once you're don't getting the gear pattern correct with the setup bearing you press on the real bearing then check the pattern again. If it's good you're done. If you need to adjust it you need a "bearing splitter", looks like the following. You put it under the bearing to hold it then press the pinion through the bearing.

1069018
 

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Discussion Starter #4
Thanks for the replies.
I got everything apart and below is a picture of my pinion gear. Based on the pattern it seems like it may have been too far into the ring gear, but I have not see a lot of these. The pinion bearing had 0.035" of shims (2 shims) under it. The head of the pinion has the stamp 373 1L5LA MOA which I am guessing it a motive gear set.
Any thoughts?
pinion gear.jpg
 

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I'd probably start with the same shims and see what the pattern looks like. I don't have enough experience to say one way or another what your images say about the previous setup. I think the following book is a pretty good reference. I pm'd you an excerpt from it showing gear pattern setup with regards to backlash and pinion depth. Also if you do end up making a setup bearing make sure you have two of the same bearings. There are two styles that will both fit in the same 8.8 housing. Ford switched to a heavy duty version with a different pitch on the bearing and race. If you use the bearing that doesn't match the race for setup you'll be completely off once you put the final bearing in. You might screw up the race too.

Ford Differentials: How to Rebuild the 8.8 and 9 Inch
Ford Differentials: How to Rebuild the 8.8 and 9 Inch: Palazzolo, Joe: 9781613250389: Amazon.com: Books
 

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Discussion Starter #6
sure enough, the bearing I just ground down has a different pitch. The beefy bearing that comes with the FRPP gears is nearly $100 by itself. Maybe I will just go with a standard bearing to match the one I just ground down.

Like all projects, this is becoming a huge pain in the azz.
 

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Discussion Starter #7
So I just went out just to clean things up and I noticed that the brand new bearing race that I installed seems to have cracks in it. In the pic you can see the straight lines going the width of the race. I rubbed my finger on the race and they are significant enough to catch a finger nail. Is this a defect?
pinion bearing race.jpg
 

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Discussion Starter #9
Thanks for the link.

I think the bearing race must be defective as well. I just got this install kit from LMR yesterday, so I will be seeing if they will make it right on Monday.
 

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Discussion Starter #10
finally got some new bearings locally and had LMR refund the cost of the bearings.

Ended up with a 0.018 shim on the pinion.
Got the differential in but wanted to see what the internet experts thought of this gear pattern gear pattern1.jpg .
 
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