Check 4 Wheel Light in 2001 4.3 V6
 

So the other day I drove to the bank to deposit my check. The truck was in 2hi when I went in and when I went back out (I shut it off & such) it was in 4lo. So I rolled down the hill to the gas station, shut it off, filled it with gas, and then when I jumped back in tried to switch it to 2hi. It wouldn't so I called my dad. He told me to move it and put it in neutral and such. So after about 10-15+ minutes of this it finally switched back into 2hi. I drove it home and switched cars but my dad didn't have time to look at it.

It hasn't switched back into 4lo, but the light blinks sometimes threateningly and I couldnt switch it into 4hi or 4auto. Also, the check 4wheel light has come on (it's an automatic) and my dad thinks it may be the transfer case.

Unfortunately I do need my car right now to commute back&forth to albany to see my friend whom is up for the week. I was wondering if anyone has had this happen to them & also if it's safe to drive it? My dad's been working late nights these days so he hasn't had the chance to look at it.