84 S10 Blazer won't go into 4 wheel Drive

[dsbike]

My son has a 84 s10 Blazer. We can shift the transfer case into 4hi or 4lo. The gearbox wines as it should but we get no front axel engage lights and the front axel is not locked in. It is dark out & we didn't have a flashlight to see if the driveshaft was turning. Any suggestions?

 

[Oliver's]

Check the vacuum on the disconnect, under the hood. Front passenger side.

 

[dsbike]

we'll check it out tomorrow. Thanks

 

[CrashKnott]

My vacuum valve was under my battery tray on the 1996.

If you want to see if 4WD will engage and you're not sure if it's a vacuum problem, you can actually "shift" the transfer case manually by getting under the vehicle and rotating the shifter (can't remember exactly, but I think it goes to the front of the truck)

...that will bypass any vacuum valve/leak questions. Kinduva PITA to do going off-road though

 

[GubNi]

Yep, it's probably that vacume ball thing. Had it happen to mine back in the day. Seems like it was a simple fix.