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Diff gear set up

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O.K, the mark in brackets is for difference in .000" b/w gear installed and "spec" gear. Froom what I understand it's used for setting pinion depth.

So, if my old gear and the new gear I'm installing has the same number in the brakcet, I can just reuse my old pinion spacer, right? I still may have to use different shims for the carrier, but I will be o.k w/ pinion depth, corerct?

it sure seems that way to me.
 
Here's what I have:

Old pinion: <.> and 005, ring gear 008

new pinion: <.> and 390, ring gear 374 BL10.11 ( 3.55 set)


Is the 390 and 374 a gear set or clearance #'s?
 
Do you have the Bentley's manual? You need to read through that. The pinion depth is everything. You have to get that right. Ring gear is just backlash and you can change that easier than the pinion that is pre-loaded with the crush sleeve.
 
I've got the BL workshop manual and it's crap. Lots of critical figures are wrong like ring gap. Book says ring gap should be .062 insrtead of .~012-.016. The old rings were .062. it also say pinion preload should be 11-13 foot pounds v.s inch pounds.

I don't trust this thing.
 
Nut torque is a lot, preload isn't. Preload is just how much effort is required to turn the pinion shaft after the nut has been properly tightened. (w/o the carrier in place) The sleeve is already crushed when it's measured. It takes a lot more torque than 11-13 ft lbs to crush the sleeve.
 
O.K, from what I've read it seems my old one is -005 off of "standard" and my new one looks to be "standard". Thats assuming the 390 is a gear set number ( that doesn't match the ring gear). It would seem to me that all I would need to do is measure the currently installed pinion depth and set the new one to that height, right?
 
Does your old set whine? You might want to run some prussian blue through those gears and look a the mesh first. If you are satisfied with that then yes. You should be able to set it like that, but you better rig up something that is very trustworthy to measure from. You will then need to put the new pinion in there and press the bearings on it and see what the shim size you need is. Then press the bearings back off and put on the shim and press the bearings back on and check and see if you got it spot on. You will likely end up doing this several times (not fun).
Once you think you have that. Put on the ring gear with whatever shims you had with the old set and check the backlash. It has to have backlash and int needs to be about .010. Once you get that then use prussian blue and look at the mesh.
You might have to reshim the pinion depth again after that and again adjust the backlash. Don't get in a hurry.
Yes, you are right with the preload of how much it takes to turn the pinion once it is tightened. I know I had mine a little too high because it took more to turn it, but if you screw up, then you have crushed the sleeve too much and have to get another one(or shim that which I have done also so you can crush the sleeve some more.
 
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