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4x4 Posi-Lok Chevrolet/GMC S Series

S-10, S-15 Pickup, Blazer, Jimmy

4x4 Posi-Lok Kit #500

Application Guide

Part No. 500
1983-2003 S-10, S-15 Pickup, Blazer, Jimmy including ZR2 and Highrider
Note: With Vacuum Actuator
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4x4 Posi-Lok replaces the vacuum actuator with a cable operated actuator that puts the driver in control of the engagement from inside the cab. After engaging the transfer case, a one inch pull of the 4x4 Posi-Lok cable connects the right front axle to the intermediate shaft using the shift collar and fork, and 4-wheel drive is engaged! Simply reverse the procedure to disengage 4-wheel drive.


Common Problems With The OEM System-Thermal Linear 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.

4x4 Posi-Lok Benefits

  • 4x4 Posi-Lok reduces front differential wear and right axle breakage.
  • 4x4 Posi-Lok provides 2-wheel drive low range, giving the vehicle 4-LO torque at the rear axle with bind free steering only available in 2-HI. This feature is not available with factory systems and is beneficial when maneuvering trailers.
  • 4x4 Posi-Lok will not disengage when ignition is turned off or the differential is submerged.
  • 4x4 Posi-Lok is compatible with manual or electric transfer cases and installation can be completed in one to two hours with basic hand tools. No internal differential work is required.

Part No. 500 Includes:

  • Heavy-duty cable system to replace the faulty OE vacuum system
  • Discreet dash mounting
  • Easy to follow instructions make installation easy
  • Complete wiring system to ensure the 4WD dash indicator light functions properly

4x4 Posi-Lok,
Copyright 2001 4x4 Posi-Lok—Patent No. 5,605,213