PosiLock 4X4 Engaging System Install

The PosiLock 4X4 Engager replaces all the vacuum aspects of your 4X4 system, insuring rapid and reliable switching
from 4X2 to 4X4 and back. One of the most common problems with stock systems is the vacuum switch on the transfer case. Second in line is failing vacuum hoses that leak and prevent 4X4 from locking in. The PosiLock system is all mechanical. It operates on the basis of using a throttle type cable to pull or push on the CAD cable connected to the front chunk. The cost is a bit high, but the benefits are well worth it.

The system can be bought from J.C. Whitney and others.

Thanks to David Randall for his contribution

Here is what is needed for the install:

• Miscellaneous metric wrenches
• 9/16" drill bit
• Drill
• cable ties to keep cable outta way of moving parts
• torx bit screw drivers to remove panels under dash
• 2 hours of free time, 5 hours to test the system (some people prefer more or less time) 45 minutes if ya have a buddy
• difficulty 2.5-3 out of 5 wrenches

Since the introduction of the S-10 style vehicles, the front ends of these very capable vehicles have always had Independent Front Suspension with the front axle being engaged by a cable/vacuum operated control system. While
the system works flawless when the vehicles are new, with age and deterioration the vacuum side starts to fail. This can lead to various unpleasant situation, for example- bragging to buddies that you can go anyway but you can't seem to make it into your driveway but your wife's/significant other's metro does. So while, some people option to replace the defective parts, which can amount to a lot of money.

Current prices-

• Vacuum Reservoir-$35-40
• Vacuum switch down by 'case-$25-30
• Hoses-cheap just a pain to replace/run
• Vacuum Actuator-$30-35

With these prices, and coupled with the facts that I live in a state that sees a lot of different temperatures throughout the year (which leads rubber parts tend to wear out a little faster than most) and I am planning on a Solid front end swap in the near future, I just opted to install the cable operated system by Whitey inc. to end my headaches.

Note: This is the same for the '83-88 style systems with the cable actuator and vacuum  reservoir is on the Passenger side fenderwell. The same kit does both types of locations including 88-00 where the actuator is located under the battery, refer to install instructions.


Locate which vacuum line is the one that feeds the switch on the transfercase off of the reservoir.  It should be about 3/8" vacuum line that runs down by the tranny dipstick. Pull off all the vacuum  lines that run to the 'case- less of a mess to
worry about and since they are useless after the system is installed, they would eventually rot  and fall of anyway. Plug off the tee with the supplied vacuum cap.

Take off the Dash panels to gain access to the mount for the Go Pedal, and proceed to drill the 9/16" hole that is need to run the cable through the supplied rubber grommet. Run the cable through and carefully  pull through into the engine compartment as to not to lose it later. Mount up the handle and make sure to make it solid (the plastic surrounding the place they have you mount it isn't that strong so use the  supports included in the kit). Reinstall the dash panels.

 <<A view of the CAD cable without the vacuum diaphragm.

Remove cable actuator from mount, remove cable clip, mount up the Bell crank plate per instructions.

Adjust cable so as the cable only has to be pulled about 1-1.5" out for the front end to be completely  engaged.

I mounted my sticker for it on the sunvisor and center console.
 

Last Modified: 7-13-05 JCH