locking hubs for a m211 or m151

i need some help. i dont know what they are or how much they are worth...

i found these on a set of gm 2.5 ton axles. they say free on one side and then you pull them out and turn 180% and push them back in and they say lock.

my buddy said that they were early locking hubs,and seen them on jeeps,scouts.but NEVER anything this big.

any info would help alot. thanks davan

here's some pics

They are what you suspect, early design locking hubs for the M211, M135 (G749) trucks. They will not fit anything else. New ones were around $450 /pr when they were available, not sure if they are anymore. Welcome to the site.

thanks alot. they are really cool

As I recall, those hubs are "Dual-a-Matics". The had a Star or Sprocket like arrangement that went on the outer axle shaft and then the levers operated a couple of round shafts that had a slot machined halfway through. Rotate the round shafts and the sprocket could rotate through the slot in the shaft. When the shaft was rotated the other way it filled the dish in the sprocket and the hubs were locked. That $450 price was back in the early 60's. I looked at a set of these for my M37 and although smaller, they were nearly as expensive. There tended to be a problem with that style of hub in that the free and lock would get rashed up and hard to read. If you made a mistake and had only one shaft engaged you usually stripped the sprocket. I opted for a set of Warn all metal hubs instead. In the early 60's Warn made a hub that fit 2.5 ton axles as well.

Oldfart

"Dual-a-Matics" thats a cool name. thanks for the info.


does anybody on here use them???

The GMC 211 series trucks had a sprague drive front end. The front axle only started pulling when the rear axles started going faster then the front (in other words - slipping), so even if you had the free wheeling hubs, things still turned in the drive line/differential.

Lee in Alaska

Lee in Alaska,
Probably the reason there are not many M211/M135 series after market hubs in use. Some reduction in rotational mass and gear drag, but nothing on the order of what could be accomplished on a conventional front drive system.

Oldfart