breaking in new gears.
 

Just put new set of 4.56 gears in the front axle of my xj. For the break in period I need to run it in 4wd right? But seeing how ny don't have much snow right now I heard running 4wd on bare roads isn't good for the transfer case. Any thoughts?

You don't have to run it in 4x4 to break in the front axle, it turns when you are in 2wd, but I would find a gravel road somewhere so that you could drive it while it is locked in 4wd, for a few miles anyway.

I figured it would only turn when the transfer case is engaged. Otherwise just the spider gears would move right?

transfer case is the point of disengagement. when you put it into 4x4 it engages at the transfer. front shaft and gears will spin when driven in 2wd.

Im gonna ask the dumb question here.. You do have 4.56 gearing in the rear axle right?

ideally you should run it for a 1/2 hour then let it completely cool down and do this for the first 500 miles. realistically you should drive it for a few miles find a P-lot make some wheel lock to wheel lock turns drive it home. at 500 miles change the diff lube and unless your getting noise call it good. when I set up gears on a customers car, I'll test drive it after and ship it.

Ya I do have 4.56 gears inthe rear. Thats prolly not a dumb question. I know some dumb *** people.lol but I have heard of people using different gear ratios from front and back but not as extreme as stock 3.11 or whatever stock was to 4.56. But anyways I bought the truck in the fall and it had broken pinion teeth. When I took it apart all there was for shims was the oil baffle. wheni tried to get a pattern it was deep even with no shims. So got a thinner slinger and added .005 and its pretty darn good. So im thinking the guy before me couldnt get deep enough with the pinion and said F it. Which thats why im doing it now. But for a 98 xj with 8.5 long arm and brand new goodyear mtrs for 1200 bucks im not gonna complain. When I fix things I want to do it right. Thats why I ask for advice when I need it.