4WD Will Not Work....Please Help

:shakehead Alright, here is my story....I have a 1998 Blazer. I was having trouble with my 4WD (http://www.automotiveforums.com/vbulletin/#) last year. I was told to check the actuator under my battery tray. I found out that it was busted and that fixed my problem. About six months ago, I would be driving down the highway or whatever and I would hear a loud roaring noise. I was told to check the vacuum switch on my transfer case. I replaced that and it took care of that problem. Now, when I try to put my vehicle into 4HI or 4LO, I hear the noise that sounds like it is kicking in, but it doesn't because neither front tire will spin. So the front driveshaft is not turning for whatever reason. I have looked at all my vacuum lines and they seem to be in great shape. I found out that somehow my oil filter had came loose and was leaking oil, which I have fixed now. The plug that I found on my front axle that I believe is called a indicator switch had oil in it. I cleaned that plug out and plugged it back in and it still didn't work. Another thing that my uncle did for me so that I wouldn't get stranded anywhere is he took the cable out of the actuator under the battery tray and zip tied it to a place in my engine. He showed me that if i pull out the end of that cable a little ways and put the truck into 4LO inside on the dash, then I will have 4LO only. No way to get 4HI until I figure this problem out. If you have any ideas, PLEASE let me know.

I forgot to mention that the 3 button switch on the inside of my truck (http://www.automotiveforums.com/vbulletin/#) works normal. If there wasn't snow outside and I didn't get stuck, then I probably wouldn't have noticed it wasn't working. Everything sounds like it kicks in and the 4LO would kind of feel like it was pulling me back like I was actually in 4LO but neither front tire or the driveshaft was spinning apparently.

HELP!

:shakehead Alright, here is my story....I have a 1998 Blazer. I was having trouble with my 4WD (http://www.automotiveforums.com/vbulletin/#) last year. I was told to check the actuator under my battery tray. I found out that it was busted and that fixed my problem. About six months ago, I would be driving down the highway or whatever and I would hear a loud roaring noise. I was told to check the vacuum switch on my transfer case. I replaced that and it took care of that problem. Now, when I try to put my vehicle into 4HI or 4LO, I hear the noise that sounds like it is kicking in, but it doesn't because neither front tire will spin. So the front driveshaft is not turning for whatever reason. I have looked at all my vacuum lines and they seem to be in great shape. I found out that somehow my oil filter had came loose and was leaking oil, which I have fixed now. The plug that I found on my front axle that I believe is called a indicator switch had oil in it. I cleaned that plug out and plugged it back in and it still didn't work. Another thing that my uncle did for me so that I wouldn't get stranded anywhere is he took the cable out of the actuator under the battery tray and zip tied it to a place in my engine. He showed me that if i pull out the end of that cable a little ways and put the truck into 4LO inside on the dash, then I will have 4LO only. No way to get 4HI until I figure this problem out. If you have any ideas, PLEASE let me know.

I forgot to mention that the 3 button switch on the inside of my truck (http://www.automotiveforums.com/vbulletin/#) works normal. If there wasn't snow outside and I didn't get stuck, then I probably wouldn't have noticed it wasn't working. Everything sounds like it kicks in and the 4LO would kind of feel like it was pulling me back like I was actually in 4LO but neither front tire or the driveshaft was spinning apparently.

HELP!
Have you checked all fuses?

Ground pin 13 and pull codes.
If any post back code no from shift button lights.

Jack her up on all 4 wheels and check all wiring on underside.
Put it in 4W and see if front drive shaft locks in.
If so check front axel for lock in.
post back what you find there.

Is the shift button light working right?
Pulling cablel should lock in front axel in 4W high or 4W low.