my 1998 GMC sierra, transfer case, will not shift out of 4w low.
I HAVE CHANGE BOTH THE SHIFTING MOTOR & CONTROL MODULE. STILL HAVE THE PROBLEM?. AND THE O2 SENSER CODE COME UP ALSO. ARE THE LINES FROM THE O2 SENSERS SUPPOST TO RUN THROU THE SHIFT MOTOR CONNECTOR?
Take the shift motor off and try to manually put it in to 2WD, you may have to block the vehicle up so all four wheels are off the floor to stop any drivetrain binding. If you are successful in getting it into 2WD then have someone turn on the key and out the 4X4 switch into the 2WD position and watch to see if the motor runs to the 2WD position, if it runs to that position then re-install it at that position and make sure the drive fits properly into the transfercase. I can't find a good picture of the O2 wiring routing so I can't tell you about yours, sorry.
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