I have a 99XJ with the auto and NP231. Every now and then when I shift into 4 part time, it will make a loud noise that sounds a bit like someone grabbing a ratchet and spinning it, except its really loud, kinda on a level of someone yelling. It only does it like once out of 20 times when I shift to 4wd but Its still a bit scary. Also sometimes it doesnt like to shift out of 4wd but will always get out within a quarter mile of leaving 4wd.

Does anyone have any ideas? Id rather not have to buy another T Case. But really dont want to have to rebuild.

I did adjust the T Case linkage by putting the T Case in 4wd, then moving the shifter to 4wd and tightening. Unless thats wrong.

 

Make sure you are shifting correctly.

Cruiser will probably paste his suggested shift method soon........

 

Fluid level & condition?

 

I may have figured it out. I did notice that it only happened on roads that aren't quite dry but not fully covered in snow. I measured the depth of my tires(same brand, model, and size). My rear tires are a bit smaller than the front tires(my inner teenager likes to spin my tires). And if I'm right the NP231 splits power 50/50 front and back. So the front tires were spinning differently than the back causing the Transfer case to disagree with me.

 

That's probably not enough of a difference to matter. I'm sure my F/R tires aren't exactly the same diameter and I can drive forever in a straight line & mild turns on dry pavement while in 4WD. Your TC may be singing it's death song.

 

Went out 2 days ago when there was lots of snow. Didn't have a single problem in 3 hours of driving around shifting in and out. Once I get my taxes back I'll change all my fluids. T case, transmission, differentials and what ever else I feel needs to be done. And buying an extra t case isn't exactly the worst thing I could do right now.