This weekend hunting i was driving in 4hi towing my quad. I switched down to 4lo and the truck acted like it was in neutral still. There was a whirling sound but it would not engage. When moved back into neutral the sound was go away. I replaced the actuator awhile ago. I went back up to 4hi and did not have any problems with that. I am not sure what do make of this issue. Any suggestions.

 

I had an issue like that a while ago and found that the shifter had an issue. The plastic portion with the detents had popped out of place, which caused the shifter not to go into the proper position to shift to the appropriate selection. I ended up completely rebuilding the shifter (including bead blasting and painting it to get rid of all the rust) along with parts from another shifter to fix that issue.

 

If it's not your shifter externally, your range fork in the t-case has worn. Typically this will cause it to also not stay in high range (2hi or 4hi, doesn't matter), so hopefully AtomicDog's experience will also be yours as it's less work

 

There was a time going up a incline it did pop out of 4hi. But it stayed back in after that for a few hours of driving up and down hills.

 

Also, check to make sure that your 4WD shifter bushings are in decent shape, too. If not, be sure to replace them to get rid of any possible deflection/slop.

Let us know what you find to be the issue upon closer inspection of your transfer case/shifter.

 

Oh and try power braking or just accelerating hard. If the t-case shifter moves left/right considerably you have a failed motor mount. That said, it may not cause the t-case to ghost shift but it certainly doesn't help anything and probably doesn't exactly benefit shifter bushing longevity