Driving Wheel Question

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revaz
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First Name: Willard
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Driving Wheel Question

Post by revaz » Tue May 21, 2019 6:00 pm

Many years ago I was led to believe that one of the rear wheels ( not necessarily on a “T”) was considered to be the “Driving Wheel”, ie. the one which transmitted most of the power to the pavement. This was accepted as being the wheel on the driver’s side of the vehicle. . My question is: is this premise in any way true and if so, what causes this circumstance? Is it because the ring gear is on that side or something about the position of the 3 spider gears. I also understand that you can have a 4 spider gear arrangement, but for what purpose? Just curious and wonder if it is more or less pronounced with the straight cut gears in a “T” rear end vs. the more modern spherical cut ring and pinions? I know here are some very knowledgeable “GearHeads” ( pun tended) out there that will prove or disprove my old time information.

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Ruxstel24
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Re: Driving Wheel Question

Post by Ruxstel24 » Tue May 21, 2019 6:19 pm

Wives tale IMHO.
An open differential drives both wheels, the one with the least traction will spin...
4 spider gears are just stronger by distributing the load across more teeth.


BobD
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Re: Driving Wheel Question

Post by BobD » Tue May 21, 2019 6:23 pm

Check out this excellent 1937 film on how the differential works. I believe this has been posted on the forum before. Good for review. https://youtu.be/yYAw79386WI


Topic author
revaz
Posts: 11
Joined: Mon Jan 14, 2019 4:51 pm
First Name: Willard
Last Name: Revaz
* REQUIRED* Type and Year of Model Ts owned: 1911 Touring, 1912 Touring, 1915 Roadster, 1922 Coupe, 1924 Fordor
Location: Oxford, CT
MTFCA Number: 7516
MTFCI Number: 15591
Board Member Since: 2000

Re: Driving Wheel Question

Post by revaz » Tue May 21, 2019 11:08 pm

I have always understood how a differential works and that the wheel with the least traction will spin, but that is not my question. Given the SAME traction at both wheels, will one ( the “driving wheel”) exert more force than the other in propelling the vehicle? If this is truly a “wives tale”, I wonder what observation would have prompted such an assertion. Thanks for your input.


Jeff Hood
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Re: Driving Wheel Question

Post by Jeff Hood » Wed May 22, 2019 12:10 am

On hard acceleration the torque of the engine twists the frame and lifts weight from one wheel while planting weight on the other. The wheel with the lighter load spins leading to the belief that it is the driving wheel since all of the power is being sent to it. The differential will deliver equal power to both wheels if they have equal traction, and all of the power to the one wheel if it has no traction.


Jerry VanOoteghem
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Re: Driving Wheel Question

Post by Jerry VanOoteghem » Wed May 22, 2019 9:21 pm

revaz wrote:
Tue May 21, 2019 11:08 pm
I have always understood how a differential works and that the wheel with the least traction will spin, but that is not my question. Given the SAME traction at both wheels, will one ( the “driving wheel”) exert more force than the other in propelling the vehicle? If this is truly a “wives tale”, I wonder what observation would have prompted such an assertion. Thanks for your input.

Truly a "wive's tale"! What prompts such assertions is the total misunderstanding of how a differential works. I have heard this "tale" told many times. In the real world, there will never be the SAME traction at both wheels. But, in theory, if there were, I would expect both wheels to spin equally.

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