Make sure all of the tires are the same size and equally inflated. Do not operate 4WD on dry pavement.
The vacuum actuator under the battery tray must receive and hold vacuum in 4WD HI & LO. When vacuum is applied to the actuator, it must pull the cable toward the actuator 1/2" to 3/4". It must release vacuum immediately, and the cable must be released, when shifting to 2WD.
If the vehicle is stopped and all wheels are on the ground, you will not be able to turn either driveshaft.
Anytime the vehicle is in motion the front driveshaft turns. In 2WD it is driven by the left front axle. In 4WD it is powered by the transfer case.
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