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Can you use just 1 rear tire on a dually?

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I was just wondering if you could remove one of the wheels on each side of a dually truck without causing any problems... . thanks in advance... garth I know about the weight issue... . but other than that???
 
I've seen people up here with duallies run their trucks all winter long with only two tires on the rear axle. They say it's easier to drive in the deep snow and ice ruts.
 
Running one offset wheel (either the inner or the outer) by itself will move the point at which the load is being applied through the tire(s) inboard or outboard by 1/2 the distance between the centerlines of the treads of the dually tires. In a dually setup, the effective point of load application is midway between the two tires. When only one tire is installed, the point of load application is at the certerline of the tread of that tire. The net effect is to move the load either inward or outward on the hub bearings of the rear axle. This can cause shortened bearing life or bearing failure - think of it as being similar to a severely reversed wheel causing failure of front wheel bearings on a car.



Rusty
 
FWIW, I saw a guy with a Phurd SuperDoody pulling a large 5th wheeler with only one rear wheel installed on a dually. I didn't think that was very smart. JMPO
 
I 'm thinking it would be okay if you used the wheels from a 2500 so it took care of the issue that RustyJC points out.
 
Originally posted by RustyJC

Running one offset wheel (either the inner or the outer) by itself will move the point at which the load is being applied through the tire(s) inboard or outboard by 1/2 the distance between the centerlines of the treads of the dually tires. In a dually setup, the effective point of load application is midway between the two tires. When only one tire is installed, the point of load application is at the certerline of the tread of that tire. The net effect is to move the load either inward or outward on the hub bearings of the rear axle. This can cause shortened bearing life or bearing failure - think of it as being similar to a severely reversed wheel causing failure of front wheel bearings on a car.



Rusty

Rusty- I respectfully disagree.

In "theory" the upward load will still be applied at the point where the wheels mount to the hub regardless of whether 1 or 2 tire are mounted. That is- would not the (same) load application be in a staright upward direction along the same line where both wheels would be? Granted only one wheel/ tire will carry twice the weight as in its former position, but the same weight is transmitted in the same direction along the same line to the hub as two.
 
Nope,

Rusty's right. It's a matter of leverage. The farther the centerline of the wheel is from the centerline of the bearing(s), the worse the stress on the bearings.



Dave
 
No, the two dually wheels generate equal but opposite torques due to the offset between each wheel's mounting flange and the tread centerline. These torques cancel each other out and make the effective center of the dually combo the plane between the wheel mounting flanges.



With one wheel removed, there is no opposite torque from the missing wheel to cancel out the torque generated by the offset of the remaining wheel. For the point of load application to remain the same as the pair of wheels, a spacer would have to be used as is used on the front hubs to move the centerline of the remaining tire into the same plane as the original plane between the wheel mounting flanges.



Rusty
 
Dave,



My "no" was respectfully directed as a response to fkovalski's posit, not to you. I believe we posted simultaneously. ;) :D



Rusty
 
DPelletier- I think you got caught in the middle.



You state that a spacer will need to be used in order to move the upward line of force. I say that a spacer will now increase the wear on the bearings becuase the end result of the upward force is farther away from the bearing's location. If I read correctly, A spacer would allow the scenerio for only an inboard tire to run solo. But, spacers, I believe, only add stress to an axle/ bearing setup. Front hubs are designed from the get go and take this into account.

*Seriously* I am not trying to be agumentative- Just trying to remember college physics as it pertains to this discussion

EDIT- In thoery, would not the spacer increase the torque to which you refer in your latter reply?
 
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When I say "spacer", I'm describing the hub adapter used on the front of my 2WD 3500. When everything is bolted up, the back flange of the hub adapter is just about in the same plane as the centerline of the "inner" dually mounted on the front. Think of the hub adapter and wheel as one piece of metal (which they effectively are when they're bolted together). At that point, they behave like a normal wheel with minimal offset - which is the whole idea - to make the truck think that a 2500-type wheel is mounted onto the front.



Rusty
 
Yes! But, is not the concept behind the "spacer" up front on a dually for matters of retaining a proper offset for tire clearence when turning as opposed to re- centering the upward forces to the hub? The front spindle on a dually is designed up to take the forces and (I think) are not the same as the respective design of a non- dual situation.

With respect to a "spacer" theory in the rear w/ only one tire- it would dramatically increase stress on the system.

EDIT- unchecked signature box.
 
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The primary purpose of the "spacer" is to put the centerline of the tire tread at the appropriate location between the wheel bearings. The front spindles, wheel bearings and hubs of a 3500 are not that different from a 2500. The only oddity is the hub adapter I mentioned that bolts between the face of the standard hub and the back face of the inner dually wheel's mounting surface. With the new SRW 3500's, the front hub assemblies just do away with the hub adapter since it's no longer needed to correct the wheel offset.



Rusty
 
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Rusty,

I figured that you're reply wasn't directed at me, yet I could not resist the urge to poke a little fun. :)



Anyway, its been stated far more eloquently than I could do, but the bottom line is; forget the adaptors and such. The force exerted is directly proportional to the distance between the bearing centers and the wheel center.



I believe the front end components (with the exception of the notorious spacer) are identical 2500 vs. 3500 dually.



Dave



ps. I'll butt out of the conversation now!
 
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