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Old 12-06-2017, 06:03 AM   #1
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Default differential questions new

ok, here's where i am.
1. following tom endy's plan.
2. carrier preload. assembled carrier with spider gear "tri-spindle" (no
3. put r. axle housing on banjo (no axle or gaskets) bolted down to 35 ft/lbs.
4. put l. axle housing on banjo (no axle) 2 thicker gaskets. bolted down and
ring gear spun freely.
5. took l. axle housing back off and added 1 shim behind the l side bearing
already have 1 shim on both bearings.
6. put l. housing back on and bolted down to 35 ft.lbs and ring gear still
rotated but did not spin. i think if i add another shim to r side (making it
2 shim on both sides is will make it too tight.
7. took axle housings off and inserted pinion gear ass'y and drive shaft in
banjo and added thrust washer and tightened large nut until i felt
resistance. initial resistance was a little more (as noted in Mr. Endy's
instructions) added locking washer and jam nut.
8. wow, carrier preload check
9. pinion preload check
10. put r. axle housing back on with 1 thicker gasket on put carrier back in
(no spider gears or axles) put l. axle housing back on with 1 thicker
11. so now i had 1 gasket on each side
12. gears clicked when when turning the drive shaft slightly in both
directions. like you can hear the teeth making contact with each other.
13. doesn't seem right. will i hear that if i fill banjo with final oil. or do i
have to redo the preloads?
14. i know this is a repetitive thread and its not helping anyone else. but
i'm stumped.
thanks for your patience and help
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Old 12-06-2017, 12:30 PM   #2
Bob C
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Default Re: differential questions new

Through out this whole process you have never told us how many inch pound
of torque you are getting on the carrier preload or what the back lash is on the pinion.

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Old 12-06-2017, 02:16 PM   #3
Tom Endy
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Default Re: differential questions new

You should not move on to setting the pinion pre-load until you have determined the pre-load on the carrier. At step 6 you still have not determined what the carrier pre-load is, however, in step 7 you move on to the pinion pre-load.

Go back and take the pinion gear assembly out and add and subtract banjo gaskets until you have the carrier pre-load set. Then take the two axle housings off the banjo and set the banjo gaskets aside. Then with just the banjo, install the pinion assembly and set the pinion preload. After you have accomplished carrier pre-load and pinion pre-load you can move on to set the back lash. Follow the instructions precisely.

Tom Endy
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Old 12-07-2017, 09:54 AM   #4
Dave in MN
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Default Re: differential questions new

I agree with Tom Endy. At step 6, if you do not have enough carrier pre-load you should remove one of the thick gaskets and replace it with a thinner gasket to increase the pre-load. You are on the right track, you just need to get the preload correct prior to moving to your step 7.

The "gears clicked" noise you describe could be normal. With a bit of clearance between the gears (backlash); when the pinion gear is rotated slightly from one direction to the other, you will feel and often hear the teeth initially making contact.

As Tom states in his Tech Article, you want the backlash to be as little as possible without teeth bottoming out. The contact pattern between the teeth should be centered between the top land (crest) and the base of the tooth. The pattern should also be somewhat centered on the ring gear between the heel (outer end) and the toe (inner end). If you are noting a contact pattern that is at the top land or crest of the tooth, you will have early failure of your gear set. Typically, with this pattern you will also have excessive backlash.

You have installed shims behind the carrier bearings so you have some ability to shift your carrier closer or further away from the pinion gear. By moving these shims from one side to the other you will be able to adjust the gear contact quite a bit. If after moving shims and gaskets you still have excessive backlash, you can install a shim between the pinion gear and the first (pressed on tapered bearing) this will move the pinion gear deeper into the assembly and lessen the backlash.
Setting up differentials correctly is not easy and it is lots of work. There is no easy way or shortcuts to do it. Good luck with your project.
Good Day!

Last edited by Dave in MN; 12-07-2017 at 04:34 PM.
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