How do Auto Hubs work?

[lonestar]

I have searched the forum and came up short.

I was trying to figure out how the Auto hubs on a 1st gen work. Right now mine still work thank god, but was doing some research and came across a thread about placing a spacer in the hub to get more travel from the cam to fully engage the hub. So as an engineer with some extra time I decided to go pull mine off to see what the hell they looked like.
Basically what I saw was a splined shaft, and the collar with the three notches. Then in the hub was a splined socket with a outside collar with three fingers which both spin on a small shaft at the bottom of the hub and held by a small split ring. The fingers in the hub line up with the notches and thats it. I figured when torque was applied the collar in the hub, it cams out the splined socket onto the shaft, or something like that. I tried to do it by hand and couldn't get anything to move in or out. But I dont see how that torque is transmitted to the wheel since both peices spin freely inside the hub.
Hopefully not on those three little fingers.

Would anyone have a exploded view of these hubs? I found one posted, but did not work.

I have seen munauls, and there pretty simple. Basically when the hubs were locked, a peice with about 8-10 fingers engaged with a peice on the shaft.
It would be nice if they designed a solid hub that had a peice that was splined on the Inside and outside. The outside splines would slide in the hub allowing the inside splines to slip up on the shaft. All the torque would be transfered by splines, though the hub and to the wheel. No thin fingers to break. You could make the splines about two inches. That would be an inch engagement on the shaft and an inch engagement inside the hub.
I know it's long, that last paragragh was an after thought.

 

[410Fortune]

The Autohubs work just like you described, as soon as the axle shaft start spinning the cam moves and engadeges the wheel and rotor to the axle. However they dont work for long!

Ditch them and get the Warn's, no more worries.
I have only heard of one Warn failure and that was on a truck with 35's and a locker, maybe we should start a poll?

 

[VOATMJ1]

Originally posted by 410Fortune
However they dont work for long!
Ditch them and get the Warn's, no more worries.
I have only heard of one Warn failure and that was on a truck with 35's and a locker, maybe we should start a poll?

I have to disagree slightly with 410Fortune. I recently got rid of a '86 BII EB, with the Auto Hubs. From the time I drove this vehicle off the dealers showroom floor in '86, until I got rid of it a few months ago, I never had any problems with the autohubs, and I live in Iowa, which means that I used the 4x4 system (sometimes heavily) every winter.

The key, is proper maintenance. I had my hubs serviced, (greased), every year, and had ZERO problems with them for 16 years!

 

[410Fortune]

Okay well first off you are correct, proper prevenative maintenence is the key to getting long life from any moving part on your vehicle.

I have an 88 BII that I have been driving for 6 years, daily. The first thing to go out on my BII was one of the autohubs, this left me stranded in a snow storm when an autohub fails the electronic shift motor will not engadge the 4hi or 4 lo,leaving you in two wheel drive. Obviously it went out at the worst possible time. I replaced the auto hubs to the tune of $400, because at the time I did not know better.

When you service the auto hubs you DO NOT use bearing grease. The hubs need to be cleaned, not greased. The best way we have found to do this is fill them with ATF and let them soak, while engadging the cam in and out over and over again, then drain the hubs and let them drip dry before re-installing. This proceedure works for both auto and manual hubs. Basically if you have your wheel off for any reason you mine as well clean your hub, even if it has only been a week or so since thelast time you cleaned them. Why not? It's quick and easy and we already know prevenative maintenence is the key to long life.


I am assuming that your 86 BII, though it may get to use the 4x4 system often, has stock size tires on it and probably 3.55 or even 3.27gears. When you run taller gears, larger tires, or a traction device the strain put on the hubs is increased a great deal.
The auto hubs are a good concept, obviously you dont have to get out to lock the wheel to the axle, but I can tell you that when they finally do fail, it will be when you need them the most. Also replacing the auto hub is outrageous, the cost is ridiculous and buying a used hub as a replacement is only prolonging the inevitable.

So yes this is my opinion but it is based not only on my own experiences with the auto hubs but also from frequenting this forum and several other BII/Ranger?explorer forums from over the last 4 years or so. Ask around and see what people prefer, auto or manual.

Again, maybe we should start a POLL, auto or manual.

FYI: my auto hubs (the originals) lasted for 150K mileson my BII, which is alot!!!

 

[VOATMJ1]

I agree with you, if my autohubs had ever gone bad on my BII when I had it, I would have changed over to manuals. But like I stated, with proper care, they lasted for 16 years and were flawless whenever I needed them.

The kid I sold it to, is really giving it a beating, off road sand hopping and 4 wheeling in the woods. I never did any of that with it, but he tell me it has been a champ and has even pulled his friends 4x4's (not a BII) out of deep stuff with it and no 4x4 problems.

Of course I was the original owner of the vehicle, and if someone bought a used one, the I would highly recommend switching over to manual hubs. (Unless the service record came with the vehicle).

Anything automatic, will likely fail more quickly than something manual, less parts.

 

[lonestar]

I agree manual hubs are stronger than autohubs, as is almost all manual operated devices. I even thought about manuals when my autos blow, but the one thing I see as ridiculous is having a auto t-case with manual hubs. I you are going manual, go manual all the way, the only problem is finding the manual t-case.
On another note. When I had my hubs off, it looked liked when the previous owner had the hubs serviced recently, they decided to use axle grease instead of gear lube. I just put it back on and figured I'll mess with it when they stop working, or the next brake job.

 

[410Fortune]

This is why I spent the last 6 years building my BII. When I got it from my older brother I was so impressed with how friggin tough the little truck was and how it would basically go anywhere without any problems, that I kept it and decided to build it. I never even wanted a 4x4 truck before that, now I'm hooked.

The manual T case is nice, converting over to one from the electric shift is a lot of work, the overhead console (older trucks) control box under the dash, and wiring would all have to be stripped out. a new hole cut in teh floor, the plate modified to fit the shifter, the shifter installed, not to mention dropping the T case. Never stopped me before but the electric shift has only failed me once and the was only for about 3 minutes (aside from when my auto hubs first went out).

 

[lonestar]

I don't think a t-case swap is that hard. I heard its pretty much a bolt in, after finding the manual t-case. Only aceessories required is the t-case plate for the floor, (get from donor vehicle) and the trans-t-case boot. And cut a hole in the carpet. Just leave the wiring in place, incase you want to sell later.

 

[punkbek3886]

my dad and i were working on my ex auto 4x4 and i left him to reassemble them when i went to school the next day. i know he used grease on them because i have had the wheels off since then. my hubs slip horribly also, and seeing this column made me wonder if i took off all of the grease, will the cams slide more freely and engage positively if i degreased them? please help me.