1989 s10 blazer 4x4 front tires won't pull
 

I've been tryin to get this 4x4 problem for a while now. When I got it the whole vacuum was tore out, so they had it to where they manually engage the front diff but they just won't engage, the indicator light comes on and the floor shift transfer case seems to engage because it changes the gear ratio in the rear wheels. Would the shifter be out of adjustment or is the front diff fork just broke. I just need a little help before I got start tearing the shaft apart. One more thing the drive shaft spins to the front diff but the front wheels don't, and I jacked the front wheels up and the spin oppisite of each other while in 4x4 and by them selves when it's not.. I would greatly appreciate any help at all. Thanks.. You can email me or call if easier it's 740 360 3615 and email is jebidiahthug1966@gmail.com

there is a vacuum actuator under the battery tray. if it doesnt have vacuum the front diff wont engage. Its time to hook all the lines back up. Autozone has free vacuum diagrams on there site.

I know all about the vacuum and that's why I asked this forum because that isn't the problem.. The actuator is completely bypassed just like the posi lock system. I'm thinking it's the collar caught up because it's not letting it engage. It used to work fine so I know it has nothing to do with the vacuum.. Thanks though

This is a pic of what I'm talking about. The actuator pulls the fork so the front axle can hook up, but I'm not sure if that is what's causing it because everything is sound there is no grinding no nothing.

This is a pic of what I'm talking about. The actuator pulls the fork so the front axle can hook up, but I'm not sure if that is what's causing it because everything is sound there is no grinding no nothing.

The cable should move 1/2" at a bare minimum, but ~3/4" is typical for full engagement. If it doesn't move that far, then there is something wrong inside the front axle.

As a test, manually engage the front axle with the transfer case in 2HI and all 4 wheels on the ground. Then try to spin the front driveshaft. A pipe wrench can be used to really ensure that it is engaging properly. If it turns, then the front axle is not engaging properly.

Ok thanks for the tip, will it help if I have someone manually engaging it while I spin the front drive shaft. That way if it's in a bind it might slip in.

Wouldn't hurt.

I finally got the front diff to lock in. I took the actuator apart from the diff and the cable wasn't pulling the rod far enough out. Thanks for the help.