Hey i have a 2000 Chevy blazer

I went to engage my 4x4High and i didn't hear any sounds but the light moved and stayed on 4x4 High , then when i went to drop it into drive, it still felt like 2wd , then driving, the light went back on to 2wd so then i pulled over again dropped it into Neutral and clicked it again both 4x4 High light and low flashed then back into 2wd, so i clicked 4x4 Low, then heard all the sounds for 4x4 Low engage

i have checked all the Vaccume lines,Fuses, wires allot of stuff and im all out of ideas. no leaks no nothing 4x4 Low works %100 just not high

I will upload pictures upon request ,Im just looking for other options on what in the fawks going on.

Cheers Brandon

 

Your problem sounds just a little different than a problem I had previously, but only a little different so what I'm going to suggest might not work or diagnose for you like it did me but there's no harm in trying, right? Disconnect the negative on your battery for a good minute and reconnect it. Does high work now? If so, then it's part of the computer (mine was $10 at a junkyard) that engages the 4x4 system. If not, sorry I wasted your time

-Brandon

 

Already tryed that, when i click 4x4 High, it makes a click sound then just wont work, then i click 4x4 low, sometimes the lights come on, some times they dont

 

I'd double check my actuator. Sounds like it's engaging the t-case but the front end isn't being locked.

I'm no expert on these things haha I'm just trying to throw out any piece of info I think might help because there isn't a lot of help that goes on here like there used to be unless you're well known here. I made this new account a couple years ago to prove that point. My old well-known account would've been replied to in ~5 minutes.

 

Its not a T case because my 4WD Low works, and no Vaccume leaks, im guessing im low on front diff fluid because i can feel grinding in the front end.
i saw this front Left diff boot leak
[Update], when im slowly rolling randomly, i put it in N and hit my 4x4 high, and it engauged normally , but then i whent into 4wd Low , worked fine, then 2wd, fine, then back to 4High, didnt work all lights went out, then clicked it again , then it went back to 2wd