GM IFS 4wd issues

[Greg]

So I learned that my front axle isn't engaging on my Chevy, (while I had an intrested buyer looking at it.) It's a 1990 3/4 Ton, 4x4.

Don't the Chevy's have some kind of electrical disconnect that has been known to have issues? Is it something simple like a plug or something more serious?

I'm going to crawl under it tomorrow, buy any info would be helpful. Stupid IFS!

 

[Rusted]

Around 1990 is when they were using a heater, that would expand a cyclinder of oil (or some liquid) that in turn would engage the axle. It was common for that heating unit to go out on them. I guess the point was "no moving parts" to engage the axles. I am not sure what year they started and stopped that idea, but think about that as you crawl under there. I may have a manual that covers that year, if I do, I will post any more info I can find for you.

 

[Greg]

Around 1990 is when they were using a heater, that would expand a cyclinder of oil (or some liquid) that in turn would engage the axle. It was common for that heating unit to go out on them. I guess the point was "no moving parts" to engage the axles. I am not sure what year they started and stopped that idea, but think about that as you crawl under there. I may have a manual that covers that year, if I do, I will post any more info I can find for you.

Thanks, that helps alot! I've heard that before, I'll have to look into the specific part and cost.

 

[Hickey]

Thanks, that helps alot! I've heard that before, I'll have to look into the specific part and cost.

yeah, it has a heat selenoid that goes out often. there is supposed to be a newer style that doesn't mess up as much.