1996 GMC Jimmy 4 wheel drive not fully engaging?

[Dagrimmett]

Same Problem

I've read this thread all the way through and it is very helpful. What I would like to know is what is the rubber boot called just foward of the Acuator Vacuum. Mine is ripped and I believe that may be my problem on my Jimmy. I know it's been a while since any posted so I hope someone sees this....

 

[Molson02536]

I've read this thread all the way through and it is very helpful. What I would like to know is what is the rubber boot called just foward of the Acuator Vacuum. Mine is ripped and I believe that may be my problem on my Jimmy. I know it's been a while since any posted so I hope someone sees this....

Its called the 4WD Vacuum Actuator, and yes when that is ripped. It will need to be replaced. http://i.tfcdn.com/img2/z79PcXUAY57...OT9XHyKi76lvYujrneTtV-ps5qOXVZBOni4A/fyVMtP8A

There used in all the 1983 to 2005 Jimmy's I go through a few of them so i foud it better for me to just go after it at the salvage yard. $10.00 gets me 3 of them giving me 2 spare lol. Just make sure there new as possible and you'll be fine.

Good luck and take your time.
Molson02536

 

[Nate1996sonoma]

Vacuum booster

JUST A FRIENDLY FYI

I'd check the good mounted vacuum booster on the drivers side FIRST!!

I am a new owner, the truck was given to me...

I must have dislodged the hose that goes to the canister while repairing the break booster and didn't realize it. This must tie in to the entire system because the minute I discovered it was unplugged, and re-connected it the 4wd worked instantly again.

Don't tear into the headlight or trans. Case lines until you check this first!!

Literally a 2 second fix!

Hope this saves some people some time!