The 4x4 Posi-Lok Advantage
4x4 Posi-Lok puts the driver in control of the 4-wheel drive engagement. No more pushing a button and hoping your 4-wheel drive engages.
OEM Systems-The Weak Link
Vacuum Actuator
The OE unit is vacuum controlled. This vacuum system is prone to failure due to frozen diaphragm, loss of vacuum, hard or cracked vacuum hoses, or complete loss of vacuum lines.
The OE unit can cause excessive wear on the differential
and/or right axle and shift fork breakage due to incomplete engagement or disengagement.
Chevy
19832001 S-10, S-15 Pickup, Blazer, Jimmy
Dodge
19851993 1500-3500 Pickup, Ramcharger, & Trailduster
19942001 Ram 1500 Pickup
19942002 Ram 2500, 3500 Pickup
Jeep
19871995 Wrangler YJ
19841991 Cherokee XJ
19861991 Comanche MJ
Ford
19972003 F-150 Pickup
Thermal Actuator
The colder the temperature, the longer it will take to engage.
If the front differential becomes submerged, the TLA temperature will cool and the 4-wheel drive will disengage.
The TLA unit can cause excessive wear
on internal components in the differential and may cause other electrical problems.
Chevy/GMC
1988-98 Chevy/GMC K1500, K2500, K3500
1992-98 Suburban, Tahoe, Yukon
How 4x4 Posi-Lok Works-The Weak Link is Eliminated
Vacuum Actuator
The failure prone vacuum actuator is replaced with the cable operated 4x4 Posi-Lok system. The vacuum actuator is removed from the front axle tube. Engaging the transfer case and pulling the Posi-Lok handle will slide the shift fork and collar to connect the freewheeling right axle to the driven left axle. Both front wheels are now engaged and pulling the vehicle.
Thermal Linear Actuator
The failure prone thermal linear actuator is replaced with the cable operated 4x4 Posi-Lok system. The cables handle is conveniently routed under the dash. Placing the vehicles transfer case in 4-wheel drive and pulling the Posi-Lok cable handle slides the shift fork and collar to connect the freewheeling right axle to the driven left axle. Both front wheels are now engaged and pulling the vehicle.
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4x4 Posi-Lok, www.4x4posi-lok.com
Copyright 2001 4x4 Posi-LokPatent No. 5,605,213