it will shift into 4wd hi when slowing down from hwy speeds to under 45 mph. I then have to pull over shift it into nuetral push 2wd switch and return to drive then its fine. its annoying and sucking major gas. help!!!!
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1998 GMC Jimmy Question: how do i locate and replace the 4wd sensor switch.
Answer #1Greg's Orange Auto (14224 Answers) , Orange, CA - (714) 361-9386globalhelper January 08, 2013, 12:45Master
scan codes and post so we can adv
Answer #2pushrod January 08, 2013, 15:02Master
There is a vacuum switch on top of the transfer case that is defective, replace it and problem solved!!
Just fixed mine, had the same thing going on. NAPA part # 7301639. Tough repair without a lift!!
Vacuum is what actuates 4x4 system!