Need advice on t-case whine...

89 xj 4.0 jb conversions HD t-case,5speed tranny.
We had alot of snow here in Ohio so I decided to go play around on the snow covered roads.While driving in 4hi the t-case whines a little but howls pretty good while in 3rd gear only.I put it in 4lo and the noise is alot less and doesn't howl in 3rd gear like it does in 4hi???
In 2wd there is no noise......
Thoughts???

Whine from the xfer case in 4WD is normal.

it didnt used to make any noise at all.......I'm worried that I messed something up because(cant believe I'm going to admit this)I swapped in a rear axle that had 3.55 gears and the front still had 3.07 because I hadnt got around to changing it yet......A few weeks later I put it in 4wd and ran a little trail behind my buddies house then remembered that I had the two different ratios!!!!

I wonder if the gearing difference was enough to mess the case up?
I'm an idiot sometimes.....:moon:

Ah, now the missing details. Yeah, you might have damaged something.

I'll admit to doing something similar. While swapping axles (3.07 to 4.11), I had it in 4wd since I had the back jacked up and that locks the front wheels. I went to turn the vehicle around after swapping the rear and forgot. I made it about 6 feet before it bound up and everything ground to a halt. No damage thankfully.

surprisingly it ran smooth......I always thought that the case would explode if driven with different ratios....IDK.
Good thing I have a lumina now to drive as a daily......I'll be able to take the case apart to look for damage.
when I split the case What should I look for?