Chevrolet Repair: Chevy Blazer 4X4 problem, chevy blazer, linear device

Question
Hi I am in England,and cant seem to get anybody to look at a problem I have with my 99 Chevy Blazer LT 4 door..vehicle has done only 20,000 miles from new ..Yesterday I tried to select four wheel drive,but light on button just kept flashing and would not drop into four wheel drive mode..same with auto four wheel drive button..other than this vehicle drives fine in two wheel drive..any ideas?  Many Thanks  Tim

Answer
Hi Tim,
99 is a little newer than any I have had to work on, sp there may be some differences I don't know about.
But on the ones I am familiar with, there is an actuator on the front axle that used to give a lot of that type problem. It is a thermal linear device, which means it heats up and expands, thus shifting a collar in the front diff.
It would just screw out, and you can test it with battery voltage.
I will give you a link or two that might help.
First is a Chevy forum, where other Chevy owners, and service techs, even service managers will see the question and answer.
It is a great site...you will love it. It is free, just sign up and log in.

www.chevytalk.org/

Then there are a couple for front acle actuators, but keep in mind, these are companies that want to sell a manual actuator, which might be a great idea, but I have kept all my trucks stock, and seldom have a problem. But one of the sites has a troubleshooting page, so at least look at it.

www.4x4posi-lok.com/PDFs/troubleshootguide.pdf

www.pirate4x4.com/welcome1.html

Good luck,
Van