Need help diagnosing 4x4 problem.

[willem445]

There is something wrong with the 4x4 in my 1980 Chevy K20. When I engage it there is a clicking noise coming from one side of the front axle and it just doesnt seem like the 4x4 works. Ive tried locking the hubs and just manually turning the front driveshaft. Sometimes I had to rotate the drive a few times before the locks would actually engage while other times I would only have to rotate it a little before it would lock in.

Any idea what it could possibly be? I plan on taking apart the front hubs to check whats going on in there but what should I be looking for? Any other things to check for?

Thanks.

[kwmech]

Like you said, take the locking hubs apart and you'll probably find that they are gunked up. Clean them up and give them a coat of light grease.

[ryanroo]

Agreed. sounds like lock outs that aren't engaging.

[willem445]

Where would be a good place to look for replacement parts if splines are broken or something?

['63GENIII]

Are they stock locking hubs or aftermarket? Rebuild kits shouldn't be that hard to find online. KW hit the nail on the head though. A coat of light grease should do the trick. I've even been told that ATF works pretty good too. I used to use axle grease and always had problems with them not working well. I think a lot of people mistakenly still do the same thing.

[Zane M]

If you end up finding damage to the original hubs, if you aren't looking to keep it factory correct(saying you have factory locking hubs), I would suggest ponying up a little extra cash and getting something aftermarket. In the end you probably won't spend much more than rebuilding the stock set up.

[swamp rat]

But what ever ya do, if ya buy aftermarket hubs don't throw the origionals out, of one side is good somebody would want to buy them.

[willem445]

Thanks for the input everyone, when I go home and have time to work on my truck again I will take apart the hubs and look for any damage. Its a stock 10 bolt chevy front end so the lockers should be stock as well. Id like to upgrade to danas in the future but right now I am on a very tight budget with school and whatnot.

[1976gmc20]

Biggest problem with front locking hubs is not using them enough. You should turn them in at least once a month and drive for a few miles (in 2wd if you are on hard road).

Many years ago, I made some handy pocket cash taking apart and cleaning the front hubs on some hunters 4wd Ford when they got up in the mountains and found their 4wd didn't work. One side was terribly rusted but I cleaned it up and greased it and put it together and it worked fine.

There is a spring that engages the hub when you turn the handle, so if it's sticky or dirty then it either won't engage at all or it will finally drop in some time later. The handle forcibly unlocks the hub mechanism, but the spring force is what pushes it back into gear.

It all makes a lot more sense when you take them apart But you might want to make sure that you lay out all the parts in the order that you remove them so you will know how it goes back together, rather than just dumping everything in a bucket of solvent at once.

[$20071k10]

your outer stubs, spindles & hubs are the same as a D44! the inner axle on the newer 10 bolts have 28 spline axle the older 10 bolts & D44 share the same 30 spline axle so most parts on the 10 bolt and D44 are interchangeable

[willem445]

Originally Posted by 1976gmc20

Biggest problem with front locking hubs is not using them enough. You should turn them in at least once a month and drive for a few miles (in 2wd if you are on hard road).

Many years ago, I made some handy pocket cash taking apart and cleaning the front hubs on some hunters 4wd Ford when they got up in the mountains and found their 4wd didn't work. One side was terribly rusted but I cleaned it up and greased it and put it together and it worked fine.

There is a spring that engages the hub when you turn the handle, so if it's sticky or dirty then it either won't engage at all or it will finally drop in some time later. The handle forcibly unlocks the hub mechanism, but the spring force is what pushes it back into gear.

It all makes a lot more sense when you take them apart But you might want to make sure that you lay out all the parts in the order that you remove them so you will know how it goes back together, rather than just dumping everything in a bucket of solvent at once.

Hopefully greasing it helps. This truck used to be the farmtruck and has around 75,000 on it of hard miles pulling horsetrailers, fixing fence etc. Then it sat for 8 years not being used at all before i got it running again. Highly doubt the front axle has been ever lubed in its lifetime.

I will make darn sure to document taking it apart so I dont have to deal with a pile of parts and an unusable truck LOL. I remember seeing some good axle diagrams in the service manual I have so that should help as well.