2008 GMC Sierra T-case Issues

[rachalker]

A while ago I got the "Service 4WD" message on my dash. Soon after, it was stuck in 2HI and every other time I went to start up, my truck would not shift into gear, all other times, the switch would prompt me to switching into 4Lo I would do this and after that I could switch back to 2Hi. My last time driving, my vehicle was stuck in 4Lo and could only drive on that, I drove down the road this way like an idiot, but I only had to go about a mile to get home. Soon before arriving though, my truck started making a screeching sound from underneath that sounded pretty bad. I did some research before the sound started and kept coming up on "encoder motor sensor" or the "accuator", but now since I kept driving on it and the problem seems worse, I'm thinking I might need to replace the shift motor or maybe even the whole transfer case.

 

I don't know much about cars, and I'm looking to fix this myself, which is why I'm wondering exactly what the issue may be. Any input would be well appreciated.

[00Silverado4x4]

It does sound like the encoder motor (&/or sensor) on the transfer case. Best bet is to get it to a shop to diagnose so that way you aren't throwing parts at it.