AVM Automatic Hub Teardown-How do they work? (1 Viewer)

[bwatling]

Interesting mechanism here (I'm not 100% on how it works but seems to make sense). These came on my Ecuador FJ40 and from what I've read, they were produced by AVM in Brazil under a "handshake" license from Warn. Sounds like they didn't last that long and both AVM and Warn went away from these at some point. I'm in the early process of switching drums out to disc brakes on the front so decided to fully take this apart. Multiple roller bearings that sit around the outside. Appears to me when the axle is engaged and turns the inside of the this mechanism, the piece behind the bearings is like a 10 sided (decagon?) and it pushed up and engages the bearings against the outside. That's the best I can tell anyway. Does anyone have experience with these? Any references, I haven't found much? I have no big 4 wheeling plans so regreased, all surfaces look good, should continue to work as expected at this point (or not work since I won't be in 4wd much. Anyway, thought I'd post the pics as I find it somewhat fascinating.

 

[1911]

Those are new (unknown) to me; never heard of them.

 

[Shark56]

I had the Warn version of those. Looks similar.
They worked pretty well but I did end up breaking one side of the "cage". My thought is they held up for mild stuff but could not handle the strain of moderate rock crawling.

 

[bwatling]

only odd thing I ran into which wasn't a big deal was that I was replacing the hub bearings/seals and needed a 54mm socket so bought one that came with new nuts/spacer thingy and tab washer (or whatever it's called) for each side on the front. I had wondered why when I took it apart there was one nut and the outer lock nut was actually a circle/disc with a couple set screws. Thought it was odd but after I put the new nuts on I realized why they had the smooth round circle, it fits inside part of that auto locking hub. Interesting. Glad I kept the parts!! All back together now.

 

[Malleus]

So it's a sprag clutch?

 

[bwatling]

Good question, I don't know what that is but looking it up as we speak

Okay, having read about those I don't think it's exactly that but think more of a roller bearing that gets push up a bit as the surface behind it that is being turned on the spindle is like a decacon shape so when it moves forward (or reverse) it engages the bearings with enough force to turn the wheel. I can't find much else on these things so that's my best guess based on what I was looking at and I didn't take it fully apart.

 

[pb4ugo]

They auto lock when you put the vehicle in 4wd. They lock when the frt axle starts to spin. I've never really took them apart, but have replaced them with traditional lockouts many yrs ago. Warn had a version that had a dial. The idea was if you got stuck in a spot in 2wd you wouldn't have to get out and lock the hubs. If it was serious it was recommended to turn the dials.

 

[bwatling]

interesting. No plans for heavy duty off road so I'll likely keep them for now understanding that if they do go bad, fixing is unlikely and will just need to move to manual locking hubs.