Four wheel drive high will not work

1993 GMC SIERRA
400,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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IAN BRILEY
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Hi, I have a 4L60e automatic transmission and manual four wheel drive on floorboard on truck. I recently got stuck in mud with no wheel drive and so I came home and did research and found my actuator was bad. so I changed it and a seal on my differential and before that actuator went bad I had both wheel high and wheel low. Now all I have is wheel low, I use wheel drive a lot. My fuses are all good and so are my wires. I recently had the entire transmission wiring harness redone and they did not mess up. Can anyone please help me figure out what is wrong?
Aug 29, 2017 at 10:42 PM
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STRAILER
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It sounds like you have a short in one of the wires or there is a power or ground that needs to be check, do not worry it will only take about an hour. Here is the wiring diagrams to help you get started (below) and a guide:

https://www.2carpros.com/articles/how-to-check-wiring

Please run this test and get back to us so we can keep helping you.

Cheers, Ken
Aug 30, 2017 at 5:01 PM