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The Free-Lock Corporation and Their Hubs

• CATEGORIES: Advertising & Brochures, Features • TAGS: , , This site contains affiliate links for which I may be compensated.

UPDATE VII: A set of NOS Free-Lock hubs included documentation stating that by December of 1973 Free-Lock had become a “Quality Division” of Dualmatic Products Company. So, I believe this suggests that Free-Lock was acquired by Dualmatic, so now the questions are 1) when did this happen and 2) why didn’t Dualmatic use the branding sooner than circa 1970 (there was a gap between the end of Free-Lock in 1959 and the re-emergence of the brand circa late 1960s or early 1970s).

UPDATE VI: I located a set of Free-Lock hub instructions that are a pre-view for a later set of near identical Dualmatic instructions. This is clear documentary evidence that Dualmatic was linked to Free-Lock.

UPDATE V: I recently packed many of my father’s tools to bring them back to Prosser. I was a regular user of them when working on my bicycles, then my jeeps. So, I thought I knew them pretty well. That is why I was so surprised and did a double take when I removed this tool from a drawer and read the name stamped on it: FREE-LOCK WRENCH …

What??? Where’d that come from? I once asked Dad about Free-Lock hubs, but he didn’t know anything about them. So, I don’t know how he obtained it.

Anyway, given the primitive nature of it, I’d have to guess it was a first generation version of the wrench. As seen below, a second, more elegant curved-design with a better branding stamp was likely introduced after this version.

free-lock-wrench-dad-karl1-lores free-lock-wrench-dad-karl2-lores

Here’s a reminder of the other version of the Free Lock Wrench:


UPDATE IV (From February 12, 2017): This page contains two later model Free-Lock hubs that resemble Selectro hubs. My theory is that Free-Lock might have evolved into the Selectro Company:

UPDATE III: Thanks to Steve, we’ve discovered an additional version. It is now number 5, which seems to be an evolutionary step between 4 & 6.

UPDATE II: Thanks to Frank Day and his grandfather Merton, who saved this rare piece, here is a scan of an eight page brochure related to the Free-Lock corporation. 

free-lock-corp-large-brochure-lores1 free-lock-corp-large-brochure-lores2 free-lock-corp-large-brochure-lores3

free-lock-corp-large-brochure-lores4 free-lock-corp-large-brochure-lores5 free-lock-corp-large-brochure-lores6 free-lock-corp-large-brochure-lores7 free-lock-corp-large-brochure-lores8

UPDATE: Thanks to Rob, we now have an “in-the-wild” photo of the slotted Free-Lock hub. I’ve also updated the post to indicate there were four slightly different designs and an additional patent that we’ve documented.

Original post on 12/19/2016:
In 1952, Aurthur Warn filed a patent for an adjustable clutch front hub that would allow jeep owners to engage and disengage their front axles in and out of four wheel drive. Warn was awarded a patent for his work in July of 1954.

The problem with these Warn hubs was that the clutch design was complex. With this in mind,  a company called the Free-Lock Corporation developed an alternative hub. In December of 1954, only six months after Warn patented his hub, Roy Requa submitted his design to the patent office.


We have yet to document this exact design on a jeep. The reason for this might be because the face of the final hub may look different than the design shown in the patent. Perhaps Free-Lock found that in practice users needed a tool to switch the hubs in and out. However it happened, soon the first Free-Lock hub was born. It probably began selling in 1955.

It seems plausible that the main driver behind the hub was James R. Lloyd. In April of 1956 he received a copyright for the term “One million 4 wheel drive vehicles need Free-Lock hubs”. Later in the year he received a second copyright, “The world’s finest and safest, Free-Lock hubs”. (View both copyrights here)

1. The 1-screw Free-Lock Hub: By October of 1956, the Free-Lock Corporation had created the large brochure above and a smaller one (yet to be published). The company also took out ads for the hub in Popular Mechanics (and possibly Popular Science, in which they did publish later). In the case of this hub, there is only one screw along the outer radius.


This example hub from Willys Tech shows almost the exact hub that is advertised in the ad. The missing item is “patent pending”. In it’s place, the company stamped “Denver” (there may be “pat. pending” below the Denver). Hence, some referred to these as “Denver hubs”:


2. The 2-screw Free-Lock hub: At some point, the company changed the design slightly, adding two screws and shifting the stamping. This became part of a co-pending application between James R. Lloyd, Sr., and Francois A. Heck, but filed by Martin E. Anderson and Jerome R. Strickland.


Here’s an example of that hub, along with the tool used to turn the hub. More photos can be seen at the G503 site. There are also photos of it disassembled there. Note that neither the hub above or below has a center screw.

denver-free-lock-hubs2 denver-free-lock-hubs3



3. The center-slot Free-Lock hub: A year later, the company was continuing to promote the hub, but by then they had added a slot screw into the center. It also shows only one screw at the edge, but it seems there may have been two screws:


Rob’s Free-Lock hub, which appears to have been manufactured in September of 1957:

free-lock-hub-4rob-3 free-lock-hub-4rob-2

Rob tells me that the center screw spins on his hubs, but doesn’t seem to do anything. And, he’s never disassembled one far enough to determine what it does. He’s just happy that the hubs work fine independently of the mysterious center piece.

A G-503 thread comment noted that a set of Free-Lock hubs had WL-57 on them. However, no pics were provided to show which type of hubs those were.

4. Free-Lock Auto-Lock 2-screw hubs non-cursive writing on tab: Around 1958, the Free-lock Corporation developed a new type of hub. It no longer required the use of the tool and was so simple even a child could use them (or so the company claimed — do we need kids messing with our hubs!). The ad can be found in the July 1958 issue of Popular Science or the December 1958 issue of Popular Mechanics.


Whether this was a dramatically different hub or just a new central mechanism for engaging and disengaging the hub isn’t clear. Thanks to herher Park for photos of his Free-Lock Auto-lock hubs:

free-lock-luther-hub3 free-lock-luther-hub2 free-lock-luther-hub1

5. Free-Lock Auto-Lock with two screws and OUT/IN with with arrows, but cursive writing on the tab. This is Steve’s hub.


6. Free-Lock Auto-Lock 1 screw hubs with minor changes and updated branding:

Here are two examples of the Auto-Lock hub that have a stylized branding of the Free-Lock name on the center piece.These hubs also have a smaller rotational piece and small tab face. In addition, the words “in” and “out” have been replaced by “free” and “lock”.  The number of screws was decreased as well, leaving only one screw on the side. Finally, “MODEL WL-58” is stamped on the face and may indicate these were manufactured in 1958. However, what the “WL” indicates isn’t clear. These photos appeared on a G503 thread:


I believe the screw is missing in this second example:denver-free-lock-hubs-type2

For reasons unclear, in early 1958 Free-Lock’s president, James Russell Lloyd filed a patent with a new company, Cutlas Tool and Manufacturing Company, in Lyon’s Illinois, while possibly still working at Free-Lock. This move suggests he left the company for Cultas

What happened to the Free Lock Corporation? I don’t know. What I do know is that the last ad I could find was published in the January 1959 issue of Popular Science.

UPDATE 2023/03/08: As of 1973, Free-Lock was considered a division of Dualmatic. It appears that under Dualmatic there were at least seven hub types sold

Lastly, we have this oddity, a hub owned by Stephano Oddo. It’s a squat, one screw that looks similar to the original Selectro, but is shaped slightly different. To me, it’s got some nicer styling than the early Selectro hub.


Looking the same as Stephen’s hubs, these Free-Lock hubs were listed on eBay in late 2020 and they were 27-spline, meaning they might be a late 1960s/early 1970s short-lived revival of the Free-Lock brand.



16 Comments on “The Free-Lock Corporation and Their Hubs

  1. Mike

    Interesting how I had never heard of the Free-Lock Hub till I heard it mentioned here. Warn hub was always the preferred hub and I think the reason was NAME RECOGNITION. Early on, Warn became JEEP APPROVED EQUIPMENT and hence it’s control of the market.

  2. David Eilers


    That’s a good point. I have yet to see Free-Lock hubs mentioned in any Jeep Approved books.

    For what it is worth, by 1959 Warn was claiming in one ad that they had sold over 100,000 hubs. That is conceivable given that there has been approx 1.5 million jeeps built by that time, let alone some of the other 4WD vehicles that began to appear. (Of course, many WWII jeeps never returned and many folks weren’t interested in aftermarket hubs, so I’m not sure what the true market for hubs was, but, to your point, Warn had a significant amount of the market).

  3. David Eilers

    Hi Luther,

    If you get a chance to take some good pictures of it, I’d love to get them. I could used a coupe high resolution photos of that later hub. Just email them to Thanks!

    – Dave

  4. Luther

    I’ll have to get my 15 year old daughter to help me. They are on a 1946 willys, my father built in the 60s.

  5. Luther

    I have tried to send you eight pics of my jeep and hubs, two different ways, having trouble sending with my I pad. If you don’t get them please let me know, I’ll try another way. Luther

  6. David Elsea

    Great info., but my hubs are different. They don’t have a center spin dial. the whole hub spins on a flange mounted to the spindle. There is a small o-ring that keeps the grease inside the hub. Anyone seen this type of hub? I need the o=rings and local parts stores don’t have them. Any help would be appreciated.

  7. David Eilers

    Hi David,

    Can you email some pics of the hubs to me at I’d be very interested in seeing them.

    Also, since this post I’ve done another post ( ) that includes 2 mores styles of Free-Lock hubs:


    – Dave

    – Dave

  8. David Elsea

    Hey Dave I really like your name. The #2 link you posted above are the locks I have. Do you know if there are service parts available. It looks like there is only a small differences in the 2 links mostly painted versus non-painted. Also there are 3 rows of 2 screws securing the lock hub on the wheel hub. One of these 2 screws is a security screw(torx w/ a hole in the center). Another question is there a warn replacement for these? Thanks for getting back so quick.

  9. David Eilers

    Yes, it’s a good name 🙂

    The non-painted one is actually a very unusual hub. The way the top is crafted is different than any other Selectro for Free-Lock hub. My theory is that it may have been a prototype.

    Here’s a history of warn hubs:
    … the early summer Warn hubs will work. The WL-2 Warn Locking Hub (several different models) is a good replacement.The Warn Lockomatic hubs should work for you as well. Any 10 spline hub should do.

    As for parts for the Free-Lock hub, it’s possible that some of the Selectro parts will work, but I couldn’t say for sure. However, even generic Selectro hub parts are hard to find. You might have to scavenge some hubs off of eBay.

  10. Tim VD

    Dave Eilers, I have a 57 cj5 with the “Denver free locker” hubs. I’m trying to take them off so I can work on the brakes. Looking for a parts break down. I have have it apart to the bolt that is threaded into the axle shaft. Cannot find a way to loosen the bolt with no way to hold the axle from turning. The brake drum will not slide over the locker housing. Any pictures or advice? Thanks Tim

  11. David Eilers

    Hi Tim,

    From you description, I’m inclined to think you are struggling to remove the bearing adjustment or locking nut? either #1 nut on this diagram ?? Sometimes, a lock washer is bent over the nut to secure it in place.

    Some directions:

    Here’s a look at a Dana 25 front end spindle and the two nuts and a lock washer that secure it: … instead of the lock washer shown in this video, as the Novak directions above suggest, you might have one that is physically bent over the top of the nut, so you may need to bend the washer flat to remove the nut.

    This is a good video on a Dana 25 front end: (and some related videos )

    I hope this info helps?

    – Dave

  12. Bingo

    Great thread. Careful about your advice to D. Elsea tho’. I bought a set of NOS Warn hubs on ebay b/c they were ten spline. They were too large, wouldn’t fit. Said LRO on the box & it turns out, they were fer the series II Land Rover. Live & learn…& turn, turn, turn!

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