what happens if 4wheel high was ingaged and drove over 150 miles not knowing
Probably not much happened, you must have been driving mostly straight or your would have found out it was in 4X4 when you made a turn. It could have helped it actually by thoroughly warming up all of the fluids and evaporating any moisture that may have accumulated. Most people forget to run the 4X4 system at least every other month just to keep things lubed up and operating properly.
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