1996 s-10 blazer Pushbutton 4wd problems

I have a 96 s10 blazer, the 4 wheel drive will not engage. I have checked the fuse for the transfer case (good). If i turn the key on and hit the 4hi button, the transfer case locks the front driveshaft in like it should, also disengages like it should. So this leads me to believe the problem is in the front differential. I have also checked the actuator underneath the battery, I have good vacuum and it pulls the cable, doesnt lose vacuum. Anyone have any ideas or suggestions on what i should look for next??? Can anyone tell me how to check the end of the cable on the differential end to see if it is working, I didnt take it apart because i didnt have any manuals.

Thanks

I too am having difficulty getting my 4Wd to engage...1993 4.3 V6 with 140,000...
I live in MN an I hear that there is a part that is thermal...and when cold like ice fishing on a lake and in 12" snow...this is when I have problems...
I do not know the answers to your questions...but wish you well...

To see if everything is working ok in the front axle, put a block under the rear wheels and jack up the front passenger side with the floor jack under the frame or lower control arm. Take out the battery and battery tray. Below the battery tray is a vacuum unit with a cable coming out of the middle of it.

Spin the passenger front tire. It should spin freely. Now put your fingers around the cable where it goes into the vac unit, and pull the cable further into the vac unit. You should feel it click in. See if the tire will spin now. If the tire won't spin you are in 4 wheel drive, and your problem is the vac unit, the cable, the vac port on the tranny or the switch. If it does not go into 4 wheel the problem is in the front axle/differential.

I just did this last week on mine, I replaced the vac unit on my 95 with a used one from a 92 (older style) it bolted right in and worked fine.

Sometimes the vac line falls off the bottom of the vacuum unit. That will also take away your 4 wheel drive.

JimQ What did it cost for the used vac unit?
Mine enters 4HI fairly easily...4LO is tougher it blinks and if I drive it will enter 4LO at times...?

I deliver mail with mine so I have accumulated a couple parts blazers. junkyards here want usually $10 or so.

They won't go in or out of 4LO unless you're stopped. Technically you have to be going less than 3mph, but stopped works best. It takes a few seconds to blink then goes in. Same when you come out of low. That's normal according to chevy, it was on the instruction CD that came with my 95.

JimQ thanks for the info...I know a guy who also has a few old blazers for parts...I live in Central MN and salvage yards we have...how tough is it to remove the vac unit? And, I will make sure I am stopped to go to 4LO...when it was not working I was trying anything...as today...I am taking my boys ice fishing...and I need 4WD...Thanks again...:o)

There is a little round spring around the vac unit where the cable goes in. pull the spring out of the slot and slide it away. the cable will come out of the vac unit now.

2 bolts inside fenderwell where the tire is. I think they were 10mm heads. Pull the vac hose off the vac unit and it's out. reassembly is the opposite, slip the cable in and then slide the spring into the slot. While it is jacked up try 4x4 and make sure the rf tire doesn't rotate in park.

hope that helps

My 4x4 is giving me problems. Every now and then when I go to push my electronic button into 4HI or 4LO the 4 wheel drive button flashes about 3 or 4 times and then it goes back to 2 wheel drive. If I keep doing this a few more times it blows the 4x4 fuse!! And then other times it works just fine. I really need to get this thing fixed, please help.

My S-10 is giving me the same problem. It won't go into 4hi at all but it will go into 4lo. It just started happening recently and I don't have any idea why yet. Any help would be appreciated.

My 4x4 is giving me problems. Every now and then when I go to push my electronic button into 4HI or 4LO the 4 wheel drive button flashes about 3 or 4 times and then it goes back to 2 wheel drive. If I keep doing this a few more times it blows the 4x4 fuse!! And then other times it works just fine. I really need to get this thing fixed, please help.
I worked at a GM dealer as a collision tech and saw our mechanics solve this problem many times. Your problem is most likely the encoder motor has stopped workin(the unit on the transfer case that engages the t-case). My 1997 s10 blazer had this same problem and after repalcing the encoder motor it worked fine. This is a fairly easy part to replace but unfortunately it is about $250 from GM. The local salvage yard here sells them for around $75. Good luck.

I fixed the problem with 4hi. I'm assuming it was a sensor problem because I disconnected the Neg battery cable for 10 min and now it seems to work fine. The transfer case engages 4hi right away and 4lo doesn't blink 3 or 4 times before engaging. I'll try it for a while and see what happens

My 93 S-10 Blazer won't shift into four wheel drive this weekend when I needed it during deer season. Most I could get it to do was blink a couple times in neutral but nothing happened. Most the time either four wheel high or low no lights at all. Lights work because they light up when first starting. What is this trick about disconnecting the battery. Does that put it into four wheel drive, or take it out and back to two wheel drive? Thanks

I am not sure, disconnecting my battery did nothing for me. If you keep trying to put it into 4 wheel drive does the light continue to blink? Does your 4x4 fuse blow? Mine does, also try on a slope with the nose pointing up hill try to put it into 4x4 then, my flashes everytime, when I point it down hill or on a level surface my 4x4 then goes in. I think maybe my front differential fluid is low, I have not had time to check though. Is there a check hole on these differentials?



My 93 S-10 Blazer won't shift into four wheel drive this weekend when I needed it during deer season. Most I could get it to do was blink a couple times in neutral but nothing happened. Most the time either four wheel high or low no lights at all. Lights work because they light up when first starting. What is this trick about disconnecting the battery. Does that put it into four wheel drive, or take it out and back to two wheel drive? Thanks