just started happening out of nowhere. clicking in the front on 4 high and 4 low flashes when trying to engage it. i need help on where to start as this is very overwhelming from everything i read

 

See if this will help - then ask any questions you have.

https://blazerforum.com/forum/tech-a...4hi-4lo-41226/

 

Turns out to be a stuck actuator cable. It is hard to pull and I have to manually help it the last half inch to fully engage after helping it the 4 low stops flashing and engages. Will replace cable

 

Great! Remember that it could also be insufficient vacuum to the servo. I would put a gauge on the vacuum hose at the servo before replacing the cable, unless you know for fact the cable is seized. The spring in the servo is pretty strong. Best wishes.