How to: replacing the 4x4 front differential actuator

[laxman21]

Well, since my 4wd drive stopped working, I decided to fix it my self.

Since my truck is a 92 and failed emissions, I decided to start with the vacuum hoses. Now I still had vacuum at the actuator i decided to replace them anyways since they were cracking and deteriorating and you can't inspect every inch of them without pulling them. That fix can be seen here:
http://www.automotiveforums.com/vbul...d.php?t=498411

Since that didn't work, onto the actuator.

Removal:

On my truck, you have to remove the battery and the battery tray to expose the culprit. On earlier models it might be bolted to the fender above the wheel well so you don't have to remove the battery.



You need to unbolt the frame from the wheel well. The two bolts are in the wheel well, no need to remove the tire.


Next, you need to disconnect the cable from the actuator. Use a screw drive to pry the spring from the slot and pull cable out.



Next, you can remove the cable from the frame by pushing in on the retaining tabs.



I skipped this step and just unscrewed the actuator from the housing and switched them out. I thought it would be easier than switching the frames out, too.



The problem:



The replacement part, $10 at the U pull it yard. Got it out of a 2nd gen truck. To make sure it was good when I pulled it, I just compressed it and put my finger over to inlet to see if it would hold the vacuum.



After removing the frame:




Now just bolt everything back up in reverse, and you are done.





BTW, this did engage my front differential! The only problem now is that the vacuum stays on all the time.

Tomorrow I replace the Vacuum switch in the transfer case. Part# 89059420

[OverBoardProject]

Another option is replace the system with a cable elimination kit. Then you'll never have vaccum problems with it again, and you don't have to engage the differential giving you 2wd low range.

It's what I'm running on mine