Alright, so here's what's goin on. I have a 97 5 spd, manual shift transfer case. I can shift through the t-case from 2h all the way to 4L easily. It engages at works fine. When I shift back to 2H however, the 4x4 indicator stays illuminated but the truck behaves as it should in 2H (as in power is only going to the rear wheels, I made sure). The only thing is that when i get up to about 55+ mph, I feel some vibrations and theres a whining sound like the t-case is locked in. I figured there was something up with the vacuum actuator on the front axle, so I replaced it with a Posi-Lok cable. Unfortunately, the light is still on and it still has the vibration of being locked in 4wd at highway speeds. Still i can shift through the transfer case easily and feel it go into every drivetrain. Any ideas of what the problem could be?