I have an issue with the 4wd in my 95 blazer s10 v6 4 door. I actually just fixed the 4 wheel drive about 3 months ago and as soon as we get our first big dump of snow, 4HI decides not to work. When I press the button for 4HI, the lights 4HI and 4LOW blink 3-4 times, and then it goes into 2HI. But the wierd thing is it will go into 4LOW. I press 4LOW and can hear the actuator under the battery engage and hear the transfer case and front axel lock in, but no sound of anything when I press 4HI. Not sure where to go from here....

 

check your vacuume hoses, all of them.