I need some help troubleshooting the 4wd on my blazer, getting stuck on the lake driving out to the ice fishing shack is really starting to suck. The 4wd does not engage when i hit the 4wd button. When i hit the button i can hear something moving, but it just dosent engage. Any ideas on how to go about troubleshooting this? I dont think it is the switch inside of the car, but something down below. Im not sure if that is an motor, or vaccum system that actually engages the 4wd. Any help would be appreciated.

I had this same problem yesterday on the lake here in MN...I got stuck in about 10-12" of snow...
After backing off the lake in 2WD...then driving on a gravel...I could hear the front end working...but, still do not know how to keep the 4WD ingauged???

I need some help troubleshooting the 4wd on my blazer, getting stuck on the lake driving out to the ice fishing shack is really starting to suck. The 4wd does not engage when i hit the 4wd button. When i hit the button i can hear something moving, but it just dosent engage. Any ideas on how to go about troubleshooting this? I dont think it is the switch inside of the car, but something down below. Im not sure if that is an motor, or vaccum system that actually engages the 4wd. Any help would be appreciated.

HI,
I had the same problem with my 1995 Blazer- the vacuum switch on the transfer case had to be replaced. I had a garage do it- part and labor was about $45.

the vaccum is common, the actuator is also very common but way more expensive. I have also had the lines running to the actuator eaten by battery acid since the lines run under the battery housing and had to have them replaced.