Yep. Does the Sound like its coming from the front passenger hub??? Time to change your transfer case switch. Dorman part# 600-500. Also check the accuator thats under your battery. There are a few great U tube video on Blazer 4x4 accuators.

 

I agree, transfer case vacuum switch leaking internally, which partially applies the clutch shaft in the RF axle. Under $20 and 15 minutes to replace it. Only the 3 button transfer cases have the vacuum switch. 4 button is done with an electro-vacuum switch on the firewall.

 

I tried to change the transfer case switch yesterday and I couldnt find it at all, Is there any other kind than the 3 hoses?

 

The vacuum switch is ~ 2.5" long, and looks like this:





The vacuum switch is above, and slightly inboard, of the encoder motor, on the driver side. The image below is an NV233 transfer case, (just like yours). The vacuum switch is visible in the image.

 

So i looked again today and it was right infront of my face the whole time, I feel a bit blind but i went to change it out and it was such a pain because it was so tight and not enough room to work with but i finaly got it and the old one was so done, anyways so far so good thank for all the help

 

Glad you got her fixed. Thanks for posting back!