i went mudding today, and when i put my 2000 blazer in 4hi, the rear dug in but my friend said the front wheels werent turning. So i put in 4low, and when i put it back in drive i felt the usual 4low tug, but when i went through the mud again i got stuck and once again my friend said the the front wheels still werent spinning, Any ideas? your feedback is much appreciated.

 

Typical problem. Try searching for "actuator", "vacuum switch", or other such keywords and I am sure you will find more than enough information to fix your problem.

 

so i figured my actuator and vacuum switch on the t-case are bad, so im just gonna replace the actuator with the posi-lock cable system that mysons95 posted. i messed with the actuator while my truck was on jack stands, and i finally got the front diff to engage, reconnected my battery and went to find some mud, well it didnt work and i got stuck again, so while i was stuck i had to remove the battery and hand squeeze the actuator to engage the 4x4, soon as i did though i got unstuck. good thing is it isnt something major like a bad t-case or front diff.

 

Well at least you have figured out what the problem is!

 

http://www.youtube.com/watch?v=UfWdMPrdPVk