My 89 v6 k1500 will not in gage 4wd in reverse
First - You are absoluty sure that it works going forwards and not backwards. Your front differential is "open" from the factory. The opposite wheel could be spinning in reverse. If you have enough jacks I would jack up all for wheels and do some quick checks. Second - If it is doing what you describe I would say that is a wierd issue and I've never heard of that happening. Does front axle light stay lit by the transfer case shifter? Does it make any noises in forwards/reverse, popping grinding etc. Try Reverse in Low range?
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