Four Hi/Lo locks up
When you put it four hi or Lo it acts like the front brakes engage and makes a Los metal to
metal grinding and the vehicle won't move. I haven't had time to check the fluids in the
differential or transfer case. Any help would be appreciated!
That's odd that it won't move at all. I've had those transfer cases apart and there's a solid shaft that runs through the t-case for the rear wheels and a cluch pack driven by a chain turns the front driveshaft. I would guess the problem is likely in your front end if it only happens in 4x4. I need more info, does it happen in 2wd at all? Best check ALL your fluid levels (front diff (75W90), t-case (GM autotrac fluid), and rear diff (75W90), but at this point, it's probably useless because it sounds like something is majorly f***ed up.
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