Can someone describe how this thing works or point me in the direction of a post that does?

I have been in 2WD for about 2 years. I had some grinding on start up until it built up some vacuum.

What was in or out up or down before I built up pressure and after I built up pressure???

Was I locked up in some way to effect ride and MPG?


Brian

 

The switch on the transfer case is likely bad. The switch is activated by the transfer case when it shifts into a 4wd mode and directs vacuum pressure to the front axle actuator under the battery tray. If you have vacuum at the actuator all of the time, the front axle is active and will cause your mileage to suffer as well as possibly some binding while turning.