Dumb lockout hub question

[Lax]

I know this will sound dumb to the hard core off-road guys but I have to ask it. What does the lockout hubs do on 4x4 or 6x6 trucks? When you engage the front wheels for off-road aren't they driving like the rears? If not, how can they call it 4x4 or 6x6? Please explain this to me and sorry for the dumb question.

 

[BFR]

a lockout hub essentially engages/disengages the wheel from the axle shaft. By disengaging the axleshaft from the wheel (traditionally on a front axle) you reduce the amount power required to move a truck down the road. You are only carrying the shaft, not carrying and spinning it.

 

[Boatcarpenter]

First of all, no question is dumb.Asking questions is how we all learn and this forum is made for that. The lockout hubs rotate to either connect the splines on the ends of the front drive axles to the hub or not. Engaged, the drive shafts drive the wheel, disengaged the wheel will not be connected to the axle. So when your front end is not engaged with the air shift, and the hubs are disengaged, no part of your front driveline is turning. If you do not have lockout hubs, and the transfer case is not engaged, your front wheels will still be turning the axles etc.There is a lot of discussion on the forum pro and con about the merits of having lockout hubs.
Hope this helps.
BC

 

[Boatcarpenter]

You beat me to it BFR!!

 

[BFR]

Also... it seems that many people use the terms lock out and locker interchangeably. A locker effectively locks the axle shafts together forcing both sides to turn at the same rate. This is very desirable in low traction situations, but tends to rapidly break/ wear out components and negatively impacts handling in high traction situations.

Edit: the above is based on a permanently locked diff (ie spool, or welded)
there ar two other types of locker automatic and selectable. IMO if its going to be driven on the street a selectable is the way to go. there was a thread recently talking about ARB air lockers(selectable). Also you can search for detroit locker to find more on automatic lockers.

Edit II:
FWIW
I have air lockers in my jeep and the difference between locked and unlocked is as big as the difference as between 2wd and 4wd

 

[Lax]

Okay. Thanks guys!! Now I'm getting it. I think. So, when my M35 has the "airshift" engaged both front wheels are pulling just like the back and everything is driving. (?)

I guess I was reading "lockout", "airlock" "air locker" as the same. I read some off-road stuff and the guys make it sound like if you don't have "airlockers" you should never even drive on a gravel road much less even think about going off road!

So as a new guy I'm thinking, how the heck has the army made it off road all these years with a regular M35.

 

[clinto]

Also, I believe lockout hubs on a deuce (or a 5 ton I suppose) equipped with a sprag type transfer would be pointless.

 

[rmgill]

Air-Shift - lever on dash to connect front axle and main driveline together to get 6x6 action)

Sprag -automatic sprag type clutch in transfercase to connect front axle and main driveline together to get 6x6 action when front rear wheels over ride front wheel speed.

Air Lockers - air controlled locking differential that locks either wheel of a given axle to turn at the same rate in the differential area (there are also cable type differential locks)

Lock out hubs - hubs that allow one to disconnect the axle shafts on a given axle from the wheels, reduces rotational motion/inertia in the drive line if it's not need. One has to get out of the vehicle and engage these in addition to selecting the air shift lever for front wheel drive

Detroit Locker - A type/brand of locking differential. This is automatic and engages based on the amount of wheel spin from one side to another.

see also http://www.therangerstation.com/tech_library/LockerComparo.html

 

[motorolanut]

It simply keeps the universal joints/shafts driver and passenger from turning/engaged and robbing power 100% of the time.. Like was stated above.. There is no dumb questions we all learn something new every day..

 

[cranetruck]

Lubrication of the differential could be an issue when the locking hubs are used...guess that would be a different subject...