Whining transfer case
 

Hey guys
I have a question. The last two times I have used 4 wheel, when I disengage it, I am hearing a whining noise from the front of the truck. It seems like it goes away after several miles, but never did this before this winter. Seems like it isn't releasing completely. Is this vacuum controlled?
2006 3.7 78,000 miles in the northeast

The transfer case is engaged and disengaged by an electric motor. If I am hustling away from an intersection that is slippery on to a dry highway, I use 4wd and then disengage. Sometimes it doesn't disengage right away, I believe because the gears are held in place by the pressure on them because of the acceleration. I don't hear the whine, but I do get a clunk when I let off the accelerator.

I wasn't sure if it was vacuum or electric. Both times it has happened, it has been extremely cold. Just don't want to screw up transfer case.
Mechanic suggested backing about 20 feet when disengaging.
Thanks for the help gator

From 4wd High, there should be no need to back up. Just let off the loud pedal and it should slip out. From 4wd Low, what works best for me is to be in Neutral, brake on, flip the switch and then just take your foot off the brake and let is roll slightly. You will hear a robotic slide and clunk. Good to go.

I wasn't moving when I disengaged. I was parked. It was needed to get to work, but was good enough for 2WD when I left. Should I wait to be moving when taking it out of 4WD?

No, for 4wd Low, it shouldn't matter, either will work. For 4wd High, stopped in neutral.

Switching from 2WD to '4 high' can be done when stopped or while driving. If done while driving, the shift will be done when you let off the gas pedal.

Switching from '4 high' to '4 low', or vice versa, you can be either rolling at 2-3 mph AND in neutral, or completely stopped, again in neutral.

It's all explained more thoroughly in the owners manual of course.

That's really as close as most people get to STOPPED at most 4-way stops around here . . . . :)

How's the fluid? New? Up to the level?

Haven't had time to check fluid. No garage and got another 6 inches of snow today. Calling for warmer temps in the next few days.