There are four basic settings when building any differential. #1 Pinion Bearing Preload
#2 Pinion Depth #3 Carrier Bearing preload and #4 Backlash. Here are the basic of pinion bearing preload.
Setting the pinion bearing preload is the final step in most differential setups. It is also one of the most confusing steps for many first time builders. Pinion Bearing Preload is basically the tension (the load) between the front and rear pinion bearings. It can be set one of two ways, a crush sleeve also known as a collapsible spacer or shims. Most Dana axle assembles use shims while the remaining 70% of axle assembles use a crush sleeve. Here are some examples of both:
Setting the preload is different for each application. When setting a crush sleeve, your goal is to obtain the proper setting the first time. If you go too far, your crush sleeve cannot be reused and must be replaced. Start by loading your front pinion bearing into the housing and seating your new pinion seal in place.
Place the crush sleeve on the pinion and load into the housing.
Use your yoke and a little persuasion to settle the front bearing on the pinion shaft.
Tip: Take your new pinion nut or pinion washer and lightly coat the bottom with gear oil. Make sure to not get oil on the threads (pinion threads get red locktite). This eases the friction created and makes setup easier. Your front pinion bearing will now be seated against the crush sleeve.
Begin running the nut down with your impact. Once the slack is gone, start with short burst from your impact, then check the rotating drag with your inch pound torque wrench. Go longer or shorter with your impact gun depending on how fast things tighten up. Take your time and be patient. It sometimes takes as much as 400 foot pound to properly set some crush sleeves.
Tip: If you do not have access to air tools. You can drill a few holes in a piece of 3-foot flat Steel and bolt it to your yoke. This will give you enough leverage to set to crush the crush sleeve with a large breaker bar or long ratchet.
Preload shims work a little differently. The shim sits on a shoulder on the pinion gear. You use your old pinion nut and begin with and about half of the supplied shim pack.
Run the pinion nut down until it stops. Check your preload with your inch pound torque wrench. If you are too loose, remove shims. If you are too tight, add shim. Keep track of what your total shim thickness is so you can fine tune the changes when you get closer to a proper preload.
Once preload is set, remove the old nut and replace it with the new one for final assembly. Tip: When you receive your bearing kit, take the pinion nut Crush Sleeve and pinion seal and set them aside. Since they are part of your final step, it is easier to remove them from your work area. They'll stay un damaged and un used.
The final step is "seating" the pinion. Crush sleeve and shim designs are the same. Use a medium weight hammer and a brass punch. Set the punch agents the end of the pinion threads and give it a medium tap. Think about 5-lbs when your doing it, that will give you an idea on how hard to hit it. Repeate the process on the head of the pinion. Re check the preload with your inch pound torque wrench. This process makes sure the pinion is seated or settled into place.
Next Month we will look at Pinion Depth and setting Patterns. Part Math, Part Art , all common sense. 
