Need Help Please!!
The frontend wont engage?... No outta wack noises or anything except the little click when the transfer case first locks in. I have locked into 4high and 4low and the transfer case is working. The front driveshaft is spinning when locked in both 4high and 4low, and not when just in 2wheel drive. So I figured I have a problem in the front diff. I checked all my fuses and they are good. I did get ****ed off enough just to look for vacuum pumps,relays ..that sort of thing. I found a vacuum pump on the passenger side of the front diff.(small round disc pump with 2 vacuum hoses)------WHAT DOES THAT PUMP DO?
My boss has a 2000 F350 powerstroke 6-spd 4x4 and we have vacuum problems all the time when in 4by like with the air-conditioner vents changing from vent to defrost on there own espesially when in 4low
I have a 1992 f150 4x4 so I know the components of the old school 4x4 frontend.
Thanks a lot guys any help would be awesome and greatly appreciated



