about three days ago I started hearing some squeaking. Happens only when I'm driving, not just sitting. Gets higher paced as I accelerate, slower when I slow down. Getting harder to shift from 2WD to 4WD. I got underneath, checked near the transfer case and saw transmission fluid (fresh and good color) all around the transfer case. Should I check anything else, or just top off the transfer case fluid level? Is it a gasket that I need to replace or apply sealant? How long would it take for a DIY?

 

Check both the trans, and t-case fluid level. Top off as needed. Monitor fluid levels there for a while, to see which one is actually losing the fluid. Take it from there.

 

Chances are it may just be a leak at this point. From my experience, drop the front drive shaft and rebuild the CV or double u-joint( heard it called both. My truck had the squeak for a while, I though it was just a front joint until my T-case cracked. I was told this joint seazing up may have contributed to my busted T-case housing, sure enough it was rough. Got the rebuild kit from Advance Auto for a little over $20 and it fixed it. My case didnpt leak before it shattered but it is only used for offroad.

Check the joint first, chances are it is the squeek you hear.