This has been going on since February. Every time I switch form 4hi to 2hi there is a mysterious noise coming from the driver vent. it is like there is snake inside it. this noise goes away after a day maybe two days. so far i replaced 4 ball joints, left and right front wheel hub assemble and right and left cv axle and the seal. I did my research and find out that if i have problem with the vacuum line, i should hear a clicking noise but this noise is not a clicking noise and its coming from the driver side vent. I have two videos that you can hear the noise. also i have the 3 button transfer case. tomorrow i will change the fluid in the transfer case and lift the car and see if im stuck in 4wd. like most people here the plastic interior makes a lot of noise and the roads in Illinois are not the greatest.
4x4 problem blazer - YouTube
4x4 problem blazer - YouTube
Thank you for your time and help

 

Potter Puppet Pals: The Mysterious Ticking Noise - YouTube
Sorry... couldn't help it.

But to me it sounds like the regular ole blazer squeaks.. idk though

 

LOL... My transfer case works. It does switch from 2hi to 4hi and back to 2hi and 4lo.

 

lOl o,o