Bad transfer case
 

I've been having an issue with 4th gear, and sometimes third. In the higher gears I'll be driving in overdrive and it will start making a grinding sound, then downshift. It did it a few times, and today I finally figured it out. I put it in reverse today and nothing but grind. I put it in drive and it went into gear perfectly, hit reverse again and nothing but grinding, and it wouldn't move. A buddy I was talking to slid under the jeep and said he could see the yoke for the front driveline rattling around. I put it into 4lo, and reverse worked perfect.
I figure it's either a bad chain or a bad planetary. I'll be throwing my spare on tomorrow. This makes 2 bad transfer cases to go with the 2 zj's I've owned. Are the stock transfer cases in the first gen zj's that bad? Or am I just getting lucky? I plan on swaping in a 242 anyway, so this probably just means I will be ruining a junk tc for the input shaft instead of my spare.

I should probably add, It's a 94 gc, and I just put a used, but vetted tranny in it and I put a quart and a half in the tc 120 miles ago, when I reinstalled it. I dont know if it was low before because I didn't check, but I lost enough fluid between removing it and turning it around cleaning it to be sure I needed to top it off before driving with it.

If it's the NP249 that has full time, neutral and 4 low, they aren't that good of a transfer case. Swapping to an np242 is a good idea.

It's the 249. I get that they get forgotten a lot at maintenence time, but they should still last longer than they do, especially on the street.

Generally they start having issues at around 150K.

Mine did good then, it's almost to 200k. I should probably get off my lazy butt and go change it. Being layed off between jobsites sucks. You get lazy if you don't make yourself go do stuff.