T-case popping out of 4H

I have a 92 XJ with 3" lift. I had installed a skyjacker transfer case drop kit, but it messed up the linkage and would not shift into 4-Lo at all with the kit on. I ended up taking it off so the drivetrain is currently in stock form. I've noticed that if I try and shift into 4-Hi when parked, it will pop back out into 2 as soon as I accelerate. However, if I shift into 4-Hi while driving, it seems to stay in just fine, and won't pop out even during stop and go driving. Not a huge concern, but sometimes it's a pain if I go to pull out on packed ice or snow and have to back up and go forward again to get it into 4wd. Any ideas on what it could be?

Have you tried re-adjusting your linkage since you took the TC drop out?

Yeah, I realigned it, I suppose I'll check it again.

loosen the bolt that holds onto the shift rail, make sure the Tcase is in 2, and the lever is all the way down, and then tighten it back up.