Locking Hubs?

[highmile]

I am only familiar with AWD found on the Outback and the Full-Time 4WD found on the Discovery. Could somebody please explain to me how these locking hubs on the Series Rover function? When would you need to lock them? What is it locking? Anybody know what kind of hubs these are?

Thanks!

[leafsprung]

Those are dualmatic hubs.

http://www.google.com/search?hl=en&client=firefox-a&channel=s&rls=org.mozilla%3Aen-US%3Aofficial&hs=kJ7&q=locking+hubs&btnG=Search

[highmile]

Are the Dualmatic Hubs similar in concept to freewheeling hubs? Do I need to engage and disengage the hubs to unwind, etc?

[leafsprung]

Hubs

Dualmatic is a brand of free wheel (aka locking) hubs. First non ad link on google:

http://www.4x4abc.com/4WD101/hubs.html

[highmile]

leafsprung

Thank you for the links! Now, I have a pretty good idea how these things work. Looks like they were also used on a lot of old Jeeps as well.

Land Rovers need to have the free wheeling hubs locked every 100 miles or so just to get oil moving around the differential, right?

Sounds like the Dualmatics were a dealer option common on many Rovers, but many folks think they are just junk. Anything to watch out for in making these things last?

[Paul Rossmann]

I had them on an 88. They worked fine. Just real quirky to spin the little levers. I'm sure there is someone on this forum who has more experience with them as I only had that car a few years, but had no problem.

[yorker]

just engage them once in a while and you'll be fine.

[leafsprung]

never seen or heard of a failure from not locking the hubs. There is no bearing at the top of the swivel only a bushing which is normally greased. Besides the axle shafts still turn some. If you arent using 4wd, you dont need to own a rover anyway.

[Pinze]

I've got an old pair on an 88..

They appear to be well built internally as well. Other than fiddling with the levers to engage/disengage, I haven't had any problems.

[leafsprung]

dualmatics are weaker than Warn M-11 or MAPs. The engagement mechanism is not very stout.

[vtsnowplow]

I have a set of the superwinch freewheeling hubs. that i bought new last summer. They look great. and work even better.

[Pinze]

I guess it's relative..

my dualmatics have lasted for 40 years or so without failure. I think that's relatively durable. I have a set of Warns, too, and haven't had any problems with those either.

[leafsprung]

Strength is relative. If you compare the internal mechanism to some of the other hubs you can tell they are not as strong. Ive seen several broken examples of most common types of locking hub. Just a few more dualmatics (and faireys) than the others. Doesnt mean they wont or dont work.

[Terrys]

I am only familiar with AWD found on the Outback and the Full-Time 4WD found on the Discovery. Could somebody please explain to me how these locking hubs on the Series Rover function? When would you need to lock them? What is it locking? Anybody know what kind of hubs these are?

Thanks!

Highmile,
I still sense you haven't gotten an answer to your question: The 'when' & 'what' part.
The AWD Outback and Fulltime 4WD Discovery are the same, Just different terms. Selectable 4WD drive systems don't have center differentials. When you select 4 WD, you are shifting transmission (via transfer case) power to the front driveshaft. Equal power is now going to each driveshaft. Without front locking hubs (or more correctly, 'unlocking hubs) even in 2wd, your front wheels will be turning you front axles, differential, and driveshaft. This is unnecessary wear to a slight degree, but also an unnecessary waste of energy. Unlock the hubs, and you aren't wasting engine output to make the truck move dead parts (in thick oil up here in New England)
Dualmatics came out with the CJ2A jeep, and were sufficient for that truck, and the 2.25 Land Rover. They won't handle much more than those two engines. They all do essentially the same thing: disconnect the wheel from the axle, but the engagement/dissengagement mechanism differs in all of them.

[highmile]

The original links that leafspring provided more than answered my original questions. Originally, I wasn't sure what I had and how they functioned, but now I think I have a pretty good idea how they function.

Thanks!