Why two speedometer cables?

When I received this car the speedometer cable was attached on the drive shaft just aft of the transmission. In the trunk was this large very long speedometer cable. I had no idea where it went or why. Now I know it hooks to the right side of the Columbia rear end. I have seen where there is some sort of conversion gear box mounted on the firewall for these two cables to mount to, I think. Not having the 'gear box' I called the Columbia repair guy in Calif. to ask about buying one. He stated if I have the speedometer takeoff on the rear axle I don't need the other cable or gear box.

My question is why two speedometer cables?

There were two options available. 1. The long cable runs from the rear axle to the speedo, no need to use the changover g/box. 2. One short cable is used to run from the clam shell torque tube drive fitting to the change over g/box on bulkhead then 2nd short cable to speedo.

Not all columbias have the axle speedo drive, thats when you use the changover g/box and two short cables, the short cable you have is probably the one used from torque tube to speedo before your car had columbia fitted.

So, with the information above is it safe to assume ( knowing what assume will get you) that this Columbia was an add on somewhere in the cars past?

Columbia 2 Speed Axles were either ordered from Lincoln with the original car order or as an add on axle by the local dealer. The factory supplied axle had the speedometer cable connection on the rear axle itself while the dealer installled axle used the drive shaft "turtle" connection to operate the speedometer cable. By 1941 when the Borg Warner overdrive became available to Lincoln owners the sale and use of the Columbia overdrive unit rapidly became obsolete. I believe the axle driven speedometer connection was dropped when the 1940 Lincoln model cars were introduced.

My '40 does confirm that too. It was built early in the 1940 model year. The Ford Archieves factory build sheet shows the 2-speed Columbia as an option included on the orig order. It has no cable connection on the back axle, just the tap behind the tranny u-joint, and has the speedometer cable gearbox at the steering column. (trivia- the Columbias were made right here in Cleveland,OH where the company was located!) Paul

I may be wrong but the picture of the speedo cable g/box on the steering column is actually a vacuum line switch which is usually there and the actual speedo cable changover box is usually mounted on the bulkhead.

I do believe 38 ShortopConv. is correct.

My bad- trying to do too much at work & home, grabbed the photo off the hard drive without thinking- a Senior Moment! Here is an accurate photo of a speedo gearbox mounted. (enough to learn on these cars, without me giving out bogus info). Hope this helps! Paul

I do believe we have conflicting information here. John Murphy stated the the factory installed axle had the axle mounted speedo drive. 40ZephSedan stated his build sheet included the two speed rear end and the speedo take off is on the torque tube behind the tranny. Someone care to clear this up.

No conflict. John said he thought the axle driven connection was dropped when the 1940 models were introduced. So it sounds like there was factory axle driven in 38.

I believe that John is correct, my '40 Cabriolet came from the factory with a Columbia Two Speed and the speedo cable attaches to the forward torque tube.

Well live and learn, Murph...it appears that 1938 was the last year for the rear axle mounted speedometer connection. The 30 and 40 Lincolns used the forward torque tube speedometer connection and a 96H 4010B axle housing. Due to the 1941 rear axle being newly widened the speedometer connection on the forward torque tube was also used for Columbia Axles ordered from the factory. The Columbia Axle used the 16H 4010 B right side axle housing. There was no Columbia Axle housing built after 1941. Borg Warner overdrive units were the units used in and after 1941...althought I have heard rumors that some Columbia Axles were used in 1942 and even after the war...probably dealer installed.