hey im putting in some 5.29s in in the rear axle of my 90 pickup and need a little info. i got my parts from trail gear including a crush sleeve eliminator. was wondering about how many shims to start with to save a little time and how much backlash the ring and pinion should have. any other tiups or tricks would help. i understand that this is a lot of setting up and checking the contact patch and measurements so getting it as close as i can the first time would be a huge help
rear diff setup
- Thread starter jgreen
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There is no "standard" on the number of shims needed. Each pinion is different. This is why gear setups take so long, lots of trial and error. Hope you have a setup bearing, makes things MUCH easier/faster.
The FSM has the specs for backlash and torques, there's also a good booklet on the Yukon site:
http://www.yukongear.com/Downloads/Manuals/Yukon_Installation_Instructions.pdf
Zuk is the man for setting up these diffs:
http://gearinstalls.com/
The FSM has the specs for backlash and torques, there's also a good booklet on the Yukon site:
http://www.yukongear.com/Downloads/Manuals/Yukon_Installation_Instructions.pdf
Zuk is the man for setting up these diffs:
http://gearinstalls.com/
First off, if this is anything other than a wheeling rig and this is your first diff, I would suggest you have a pro do it. That said, diffs aren't as bad as folks make them, just have some serious and expensive consequences if done wrong.
Anyway, one tip I have seen used is to use a dremel or something similar to open up the original inner pinion bearing so that it can be slid on and off easily and use that as a "setup bearing" and then once you have the depth where you want it, press on the new bearing.
A spanner for the carrier adjusters is a must. The carrier bearings need around 100 ft-lbs of preload for good service life. Get you an inch-lb torque wrench to check pinion preload.
Check out www.gearinstalls.com ; ZUK has tons of installs documented that you can read thru.
Take your time and be prepared to fiddle with it a lot and you should be fine.
Anyway, one tip I have seen used is to use a dremel or something similar to open up the original inner pinion bearing so that it can be slid on and off easily and use that as a "setup bearing" and then once you have the depth where you want it, press on the new bearing.
A spanner for the carrier adjusters is a must. The carrier bearings need around 100 ft-lbs of preload for good service life. Get you an inch-lb torque wrench to check pinion preload.
Check out www.gearinstalls.com ; ZUK has tons of installs documented that you can read thru.
Take your time and be prepared to fiddle with it a lot and you should be fine.
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Good post. A bad installation will cost you a gearset, and a headache. They aren't bad, but if you aren't familiar, it can be frustrating.
Very true about costing you gear set, and usually it will grenade when you are across town or miles from anything. I am working up to my first full setup. I have "re-done" several now and I pretty good at setting backlash, and pinion and carrier pre-load, but don't have a press so haven't tried a full install.
Adding to my previous post, a press and bearing splitter are also on the need to have or have access to list for a good setup in my opinion.
Adding to my previous post, a press and bearing splitter are also on the need to have or have access to list for a good setup in my opinion.
Jynx, just putting this as a disclaimer so nobody thinks I'm bashing your ideas. Just putting out things I've heard, seen, or experienced myself. I'm only trying to expand on some of what you've said, not to disprove or contradict anything. 
Set up is very important to do right, but very tedious to do right. Set aside a good chunk of time and have a lot of patience stored up. At least as important, maybe even more so, is the break-in. If this is a street/highway/DD truck, break-in is critical to be done properly; research it and don't cut any corners. This could be the difference between a 10,000 mile diff and a 500,000 mile diff IMO.
This works but be aware that the new bearing and the old bearing MUST be the exact same bearing and preferably even out of the same manufacturing batch or else their dimensions may not be exactly the same. Just look at the thicknesses of the shims being used and realize that bearing manufacturing tolerances are not to that degree.
I recently had a diff explode at Katemcy and Marlin helped me set up a new diff right there on my trailer. He used a hammer and a punch to adjust the carrier bearings and didn't seem sketchy at all nor all that detrimental to the adjuster either. Spanner would be the correct tool, but not really a necessity if you're only setting up one diff.
This is certainly the way to go so the tool can be used for other purposes but just in case people don't know, there IS a torque tool for measuring rotational force called a torque METER. Very similar to a torque wrench, but with an adjustable dial gauge and no click feature. Again though, not recommending to go get one for one diff setup, just trying to be informative so you know all the options - high and low cost.
^^^THIS!!!^^^