CHEVY (CK 2500)

1989 Chevrolet Truck

I have a 89 chevy truck 4x4 CK2500. When I engage the 4 weel drive the front weels will not spin. I supposed to have an automatic locking system but don`t work. Does anybody out there knows how to fix this problem? Should I install the mechanical hubs on it?
January 11, 2006.

IFS 4x4s have a diff actuator in the front diff, GM had some problems with it

Jan 11, 2006.
Ck for vacuum at the servo. If u push the servo in does the front hubs lock?

May 18, 2012.
Read mileage wrong its 73500

Jun 3, 2012.
Have u checked the servo yet

Jun 3, 2012.
Please help me someone is this an expensive fix

James Humphreys
Jul 13, 2012.
When u shift to 4wd there is a vac. Servo under the hood. This has a cable that locks the front hubs. Sometimes the little clip from the servo to the cable. The clip brakes at the servo. When you switch to 4wd the servo sucks in and with that broken clip it doesnt pull the cable to lock the front hubs. Just go to the cable. Pull it to lock the hubs use vice grips to hold the
cable. Then test the 4wd. If your truck doesnt have this sys. Mail 2CarPros Jack. My sons had a 84 chevy it had this type sys.I cant see them redisigning a whole different sys. Gl

Aug 8, 2012.