I know yall think this thing is magic, and in many ways it is, but you cannot and I mean CAN NOT shift any vehicle from 4 LOW to 4 HIGH or vice versa at any speed overall crawl. If the computer forces it to happen at say 20 MPH it will be followed by a loud bang. It could be accomplished with a clutch or super synchronizer of some sort but the would make the transfer case much larger and require replacement eventually.
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