I have a 1994 S10 Blazer with 4.3 Vortec engine. My 4X4 is not working properly. It is sort of intermittently working. When I depress the 4X4 LO position on the switch, there is no indication of anything happening. When I put the transmission in nuetral and actuate the switch, I hear the TCCM activating and then both lights (Lo & HI) light up on the switch. But I can tell that it is not really in 4X4 mode. I have even forced it into 4X4 as per the manual by going from nuetral into park while the switch lights are are flashing after being depressed. I have gotten it to work normally when I had disconnected the battery (to do some other work) and reconnected it afterwards and just for S & G's decided to try to use the 4X4. But then the next day, when I tried to activate it again, it did not work. So do you have any idea what the problem can be?

Your transfer internal linkage may be dry from not using it, making the little electric motor ($600.00 actuater) that shifts the transfer work hard, shift it in and out while your running it to lube that linkage. I cut a hole in my floor board and shift mine with a 8" cresent.

The problem with your 4x4 is a broken vacumn line usually found under the battery tray. the 4x4 switch on the trans is a vac. sw. if you lose vac because the batt.leaked fluid you won't had 4x4.

I have a 1994 chevy s-10 4x4 blazer with the 4L60E tranny. Prior to warming up the tranny shifts o.k. but when warmed up it goes into neutral mode and I have even had fluid blow out of the breather tube. Can you determine the problem for this?

If I'm not mistaken, there should be a module or relay. Not for sure where it's at. Heard of these going out and not being able to switch into 4 wheel drive. I know on a 200'? Ford F-250 they have a motor on the side of the transfer case. That switches it into 4 wheel. Signal from 4x4 switch is sent to module then to the motor that engages the transfer case. Hope this makes sense. Hope this helps.