iced98lx
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Often times the thermo actuator to lock the front hubs in the front axle goes bad. Symptoms include after shifting into 4x4 the light never lights up to notify you, and you don't have 4x4. The part can be had for $65 or so online here: AM-AutoParts.com. I paid $130 from a local part supply house because were were slated to have a large blizzard the next day.
This is a VERY easy fix and anyone with a 15mm socket and a large adjustable wrench can do the replacement!! I also like to have a buddy to shift into 4wd while I'm watching the actuator and some beer naturally.
To get at the part jack the truck up on stands until you're comfortable under the truck (I had the front tires 3-4 inches off the ground). Take off the skidplate if eqquiped- it's 4 15mm bolts. I threw some wd40 on them and had a beer before going at them: they came out very easily for a 1995.
With the skid plate off and the new part in hand look on the right side of the front diff in front of the axle. You'll see the identical part, follow the wire, and unplug it. You'll have to remove the wire from the clip, as the actuator side of the wire is what's clipped to the frame- just push up on it gently.
Using a large adjustable wrench remove the acutator. Chances are it's covered in grease/fluid as it burst and is no longer usable. to test, plug it into the plug, put the vehicle in the "ON" position (DO NOT START THE TRUCK!) and move the shifter to the "N" position. Chaulking the wheels prior is a good idea. Shift the 4x4 lever into 4Hi - hold the actuator by the wires, not the body: it will get warm. If the actuator doesn't pop out after 30 seconds you've most likely found the culprit. Shift back to 2Hi, unplug the old actuator, and plug in the new.
Shift to 4Hi- if the plunger slowly moves out wait for it to illuminate the 4x4 light in the cab and then shift to 2hi and watch it go back in: you've found the problem and are about to fix it! If it doesn't come out after 15-30 seconds, you actuator isn't the issue. Inspect the old one- if it looks good you may consider putting it back in and returning the new, otherwise continue the installation and troubleshoot the problem further afterwords with a part ruled out.
Unplug the actuator, thread it gently in and tighten with no more than 15ftlbs of force- read:hand tight. plug the wire in and clip it to where the old one came off. Reinstall the skid plate, take the truck off stands and celebrate your fixed truck.
This is a VERY easy fix and anyone with a 15mm socket and a large adjustable wrench can do the replacement!! I also like to have a buddy to shift into 4wd while I'm watching the actuator and some beer naturally.
To get at the part jack the truck up on stands until you're comfortable under the truck (I had the front tires 3-4 inches off the ground). Take off the skidplate if eqquiped- it's 4 15mm bolts. I threw some wd40 on them and had a beer before going at them: they came out very easily for a 1995.
With the skid plate off and the new part in hand look on the right side of the front diff in front of the axle. You'll see the identical part, follow the wire, and unplug it. You'll have to remove the wire from the clip, as the actuator side of the wire is what's clipped to the frame- just push up on it gently.
Using a large adjustable wrench remove the acutator. Chances are it's covered in grease/fluid as it burst and is no longer usable. to test, plug it into the plug, put the vehicle in the "ON" position (DO NOT START THE TRUCK!) and move the shifter to the "N" position. Chaulking the wheels prior is a good idea. Shift the 4x4 lever into 4Hi - hold the actuator by the wires, not the body: it will get warm. If the actuator doesn't pop out after 30 seconds you've most likely found the culprit. Shift back to 2Hi, unplug the old actuator, and plug in the new.
Shift to 4Hi- if the plunger slowly moves out wait for it to illuminate the 4x4 light in the cab and then shift to 2hi and watch it go back in: you've found the problem and are about to fix it! If it doesn't come out after 15-30 seconds, you actuator isn't the issue. Inspect the old one- if it looks good you may consider putting it back in and returning the new, otherwise continue the installation and troubleshoot the problem further afterwords with a part ruled out.
Unplug the actuator, thread it gently in and tighten with no more than 15ftlbs of force- read:hand tight. plug the wire in and clip it to where the old one came off. Reinstall the skid plate, take the truck off stands and celebrate your fixed truck.
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K so i got the same thing --bad acctuator. mine is original eqip the one i recieved is the newer better one. it has a brown wire that is post ta go to cir. 24. im not to good with diagrams so the one i got with my part from the gm store is greek to me. just exactly where is cir. 24 in the fuse panel. in the cabin or under the hood? a pic would be cool cuse like most guys im totally visual when i do things! show me a pic and i got it, give me a diagram and im lost
