I just got done setting the gears on a front dana 30 out of a 1990 YJ but need a little help and/or suggestions.

I set up the gears using all the right tools (press, dial indicator, etc.) The backlash is perfect, pinion bearing preload is good, wear pattern looks good. Problem is when its all put together, it is very hard to turn the whole assembly. It takes 18 ft/lbs to turn the pinion.

When I set the pinion bearing preload I did it with the carrier out of the diff. Am I doing it the wrong way? What is causing it to be so tight?

How can you set preload without the carrier inside the diff?:confused: You add shims to move the carrier,(IE add and subtract backlash) then set preload with the overall combination of shims...Sounds like you got too much preload...

You did it right so maybe pull out the pinion, put in the carrier and see how much force it takes to turn it alone. But it sure sounds to me that there needs to be another pinion shim.

Originally posted by Gozuki
How can you set preload without the carrier inside the diff?:confused: You add shims to move the carrier,(IE add and subtract backlash) then set preload with the overall combination of shims...Sounds like you got too much preload...

the way I understood it was done is to add or remove shims from the pinion that go between the bearing and the collar on the pinion. I didn't think pinion bearing preload included the torque it takes to rotate the diff :confused:

I didn't think pinion bearing preload included the torque it takes to rotate the diff

It doesn't. Pinion preload is just what it says, preload on the pinion without carrier installed. You did it right. Carrier preload is for the carrier bearings, and it should be shimmed as tight as possible. The carrier should require a significant tug to remove it. Just adjust your shims left to right to get the correct backlash. Did you remember to thoroughly lubricate your bearings with oil? I use 10w30 or whatevers on the shelf to lub them all out. I put it everwhere. Try that and get back to us. If the axle is out of the vehicle, you could also call a local gear installer and ask him to check your work. Some guys are cool and won't charge ya. Tell him you did it yourself because you wanted to build the entire vehicle and you don't plan on going into business or anything.

Chris

took it all apart this morning and everything still checks out individually. I put 1 more shim on the pinion to loosen it up a little and it now only takes 17 ft lbs to turn.

Its all to spec so I guess thats how it should be, fawk it, its going back under the Jeep now