Overdrive

[markmp1]

This is a picture of the overdrive on the rear axle of my 1931 Deluxe Roadster. It is activated by a lever between the stick shift and emergency brake. Does anyone have any information about it? Thanks!

 

[Herb Concord Ca]

I think that is a Columbia O/D. uses vacuum to operate it. Don't know much about it.

 

[Gene F]

BTW, does it work?

 

[Bob C]

That looks like Twin-X. Highway Speed 2.84:1, Traffic Speed 3.93:1.
There is a picture at this link. https://www.fordbarn.com/forum/showthread.php?t=176490

 

[Ray in La Mesa]

Not Columbia, could be a Twin-X like Bob C says.

 

[mcgarrett]

How is it shifted?

 

[AzBob]

Looks similar to a Ruckstell 2 speed axle for the Model T.

 

[markmp1]

There is a shift lever between the stick shift and emergency brake which is pulled back to engage it. (They are connected via a steel rod)

 

[markmp1]

It works well, essentially giving you three higher gears when it is engaged.

 

[old31]

Very curious.

How in the heck does a 2 speed rear end work? When you pull the lever back, what is happening internally to make the gear change? How does it jump from one pinion to the next?

 

[katy]

As AzBob said, it looks similar to a Ruckstell which has a planetary gear set in it.

 

[Jeff in BC]

Here's an ad from Montgomery Ward Winter sale flyer ending Feb. 28 1929.
I know this is for a T or TT but they may have been made for A and AA as well.
I included the whole page just for fun.

Jeff