1999 Chevy Blazer when you put it into four wheel hi-lo the front drive tran does not engage what is wrong?

Answer 1

1. broken 4WD shift linkage 2. hubs not locked 3. hubs not locking (vaccume leak) I have a 96 blazer and the vacuum actuator, located below the battery tray, had a vacuum line disconnected. I have had several friends who had their actuator go bad. The acuators were actually a recall they have since replaced them with a newer and better model they usually went bad if not used for a number of years.

Also check the vacuum switch on transfer case as it has a check ball and can sieze up $15.00-$20.00 part. these are usually the first to go and if left to long the Vacuum actuator Abt.$50.00 can collect fluid and disentegrate, they also just go bad.The encoder motor is a solenoid Abt. $200.00 part and can sieze up as well, these are prices from a store like Auto Zone and are not from GM and do not include labor. I have learned that you need to use your 4X4 on a regular basis when you have electronic push button. I engage my 4X4 going down dirt roads and sometimes down rocky or dirt driveways. This helps keep the parts freed up and working.