Having problems with your 1999 GMC Sierra ?
4WD will not engage any more, for awhile it would work sometimes but not any more .The light on auto4x4 will stay on but the light on 4high and 4low will just blink any idea's?
The solinoid the that engages the 4wd in your transmision is broke, its an easy fix and should cost more than 100 bucks.
Repair Help & Product Troubleshooting for 1999 GMC Sierra
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