My 98 4x4 Blazer wont go into 4wd, The lights all flash then it reverts back to 2wd hi, But it locks in the front end so when you drive forward it feels like both front tires are flat and fighting each other, Lastnight i hit the 4hi button just to see if some miracle had happened and it would work.....NOT
Forgot all about it and then tried to go to a house fire last night and the front end started doing its thing, I ended up backing up over a 1/4 of a mile to get it to where i think its back to normal....This is a unmodified stock Blazer.
I use the Blazer for nothing but going to fires and in a perfect world the 4wd would work, But this thing with the front end kills me because i dont know whats wrong with it.
After reading other post, The HVAC vents all work normal as they should.
Its been to cold to pull the battery and tray to see if the accuator is working, Hope to do it today or tomorrow.

 

Take a look at this thread. https://blazerforum.com/forum/tech-a...ill-help-7180/ It might help you out.

 

Still didnt touch on what was causing the front end to act like it did.
When i find that problem i will also look at the vacume lines.