4x4 SYSTEMS-TOUCH DRIVE
The Touch Drive 4x4 system functions in three modes. In Two Wheel Drive mode, power is delivered only to the rear axle at normal road speed. The 4H position provides four-wheel drive with power delivered to the front and rear axles for increased traction. The 4L position provides four-wheel drive with power delivered to the front and rear axles when the above average power is required at reduced speeds. Four wheel drive operation (4x4 or 4x4 LOW RANGE) on dry pavement is not recommended.
Operating the vehicle in four-wheel drive on dry pavement will increase noise, vibration, tire wear, decrease fuel economy, and make four-wheel drive disengagement difficult for the transfer case.
Touch Drive system indicator lights
A 4x4 indicator light and a LOW RANGE indicator light are located at the lower right of the instrument cluster. In addition, two small amber lights are located near the Touch Drive system buttons. The amber light to the left of the 4x4 button will light up at the same time as the 4x4 instrument panel light. The amber light to the left of the LOW RANGE light will light up at the same time as the instrument panel LOW RANGE light.
❑Two Wheel Drive mode — Neither the 4x4 nor the LOW RANGE lights are lit.
❑4x4 mode — Only the 4x4 light is lit.
❑4x4 LOW RANGE mode — Both the 4x4 and LOW RANGE lights are lit.
To shift from Two-Wheel Drive to 4x4:
To shift into 4x4, push the 4x4 button located on the instrument panel. This shift can be done at a stop or at speeds up to 55 miles per hour (88 km/h). When the vehicle is driven, the automatic locking hubs will engage. If the
vehicle is stopped while in 4x4 and the vehicle direction is reversed from the previous direction, the automatic locking hubs will momentarily disengage and reengage. The automatic locking hubs may click as they automatically engage in the new direction.
Touch drive electric shift switch
— At extremely low temperatures, it may be necessary to slow down or even stop to shift from two wheel drive to 4x4.
— The initial shift from two-wheel drive to 4x4 while the vehicle is moving can cause some momentary clunk and ratcheting sounds. This is the front drivetrain coming up to speed and the automatic locking hubs engaging and is not a cause for concern.
— Because of possible damage to powertrain components, never shift from Two-Wheel Drive to 4x4 with the rear wheels slipping.
To shift from 4x4 to Two-Wheel Drive:
Push the 4x4 button; the 4x4 lamp on the instrument cluster will go out indicating the vehicle is in Two-Wheel Drive. This can be done at any speed. To disengage the automatic locking hubs, operate the vehicle in Two-Wheel
Drive in the opposite direction for approximately 10 feet (3 meters) in a straight line
If you were driving the vehicle forward in 4x4, the automatic locking hubs will
disengage the next time the vehicle is driven in reverse in Two-Wheel Drive for approximately 10 feet (3 meters) in a straight line.
If you were driving the vehicle in reverse in 4x4, the automatic locking hubs will disengage the next time the vehicle is driven forward in Two-Wheel Drive for approximately 10 feet (3 meters) in a straight line.
Operating in two-wheel drive mode with the hubs locked increases fuel consumption, noise, vibration, and wear. For prolonged two-wheel
drive operation on dry pavement, disengagement of the automatic locking hubs, which is not required for two-wheel drive operation, stops all movement of front-wheel drive components while operating in two-wheel drive. To shift from 4x4 to 4x4 LOW RANGE:
Stop the vehicle and place the automatic transmission in NEUTRAL or depress the clutch on vehicles with a manual transmission. Push the LOW RANGE button on the instrument panel to shift the transfer case from 4x4 to 4x4
LOW RANGE. Both the 4x4 and LOW RANGE lights are now lit.
NOTE: The vehicle must already be in 4x4 before pushing the Low Range Button.
[To shift from 4x4 LOW RANGE to 4x4:[/B
Stop the vehicle and place the automatic transmission into NEUTRAL or depress the clutch on vehicles with a manual transmission. Push the LOW RANGE button on the instrument panel to shift the transfer case from 4x4 LOW RANGE to 4x4..."
Using the link and information that kf4amu provided, I determined that the speed sensor in the transfer case was bad and was not allowing the truck to go into low range. It may be a a Jerry-rigged solution but for a permanent or temporary fix you can wire in a 225- 275 Ohm resistor between the harness and the sensor. This will bypass the sensor itself and provide the module with the correct ohms in order to activate 4 low. Just make sure that from then on when you go into 4 low that you are at a complete stop.