I have a 2000 chevy blazer 4wd and i'm having problems with the 4wd when I select the 4wd it works non of the lights blink but when i step on the gas the front wheels feel hard to turn and after a while the 4wd service light come on, I don't know if it's a problem with the TC or the differential or I don't know I've been having this problem since I bought it. I hope someone can help me :/

 

Me personally i would start by changing fluids and checking to see what comes out. If possible use a little mechanic video camera to get in and look at the front diff and transfer case.

 

ok, so i changed the fluids and it feels a lot smoother when engaging the 4wd and when I step on the gas it felt smooth for a while but later it felt like the front wheels didn't whant to turn, and I don't know what can it be. I did a research on the internet and found tha might be the transfer case encoder motor but I don't know, what do you think?

 

I would go straight to the connection cable to the Transfer Case ControlModule (TCCM) before replacing anything and see if it is full of corrosion. Thesevehicles have a big problem with this and I’m surprised that they have not donea recall to have these replaced with something that does not corrode.

It usually gums up the connections so bad after years of use that they do not function any longer.