4WD Vacuum Question

[Wrangl3r93]

Ok this isn't another, "My 4wd doesn't work what could it be thread?" I'm looking at putting a lunchbox locker into the front of my jeep and have a few friends looking at welding their d30's. I'm looking for a way to minimize the turning problems that come with locking the front. I know you can go with the cable style system to engage/disengage the 2 piece axleshaft but I'm looking for a way to actuate the vacuum from in cab. The wiring diagram isn't very clear on how the transfer case actually activates vacuum to shift the fork in the axle. I've found a 4wd switch but none of the wires coming off lead to a vacuum pump in the diagram.

P.S.- I'm just looking for the understanding on how this system works, not your opinions on whether I should or should not follow through. This is the technical forum after all

 

[Bounty__Hunter]

the front disconnect works simply by supplying vacuum to either one line or the other, pulling the vacuum diagram in either direction.

The vacuum switch at the transfer case has 4 ports, a vent that runs to near the battery, the vacuum source from the manifold, and 2 lines to the front axle.

I ran a manual vacuum switch to the front axle for a while, it's the 4wd switch from a full size Wagoneer or Grand Wagoneer with Quadratrac 4wd. It's a nifty little lever similar to your fan speed switch for your heater, has one input vacuum port and 2 outputs, operates the disconnect switch perfectly.

You may also use the vacuum switch found in CJ's with the Quadratrac 4wd, but haven't done it myself.

 

[SteelHeadz]

That's a cool trick Bounty, I never thought of that.

 

[Wrangl3r93]

Awesome that's the information I was looking for. Now where do I find one of these wagoneer 4wd switches? Are they available at a parts store and I'm just not typing in the right key words or are they a junkyard only option?

 

[Bounty__Hunter]

Junkyard or places like Ebay: Jeep Grand Wagoneer transfer case vacuum shift switch:eBay Motors (item 370182518558 end time May-18-09 19:30:00 PDT)

 

[Keith__C]

your local Autozone should have them in stock in the Help section, the one here does.

 

[Bounty__Hunter]

I've seen the vacuum switches for the transfer case in the help section, I'll have to look for any others.

 

[south7069]

put a posi lock on there