1957 Ford Automatic Transmission Question(s)

[Anonymous]

I have a 57 Custom with an automatic tranny. Now, from what I have read, the FordOMatic is a 2 speed transmission. When I am driving, I get a shift at around 38-42mph and that's it. By the time I am cruising at 65 or so, she's screaming pretty good. I really can't go much faster than 70. Granted, the engine is in need of a rebuild, but still...

Is that all you get with the 2-speed AT (one shift) or do I have a problem? I am assuming that it's correct with gear 1 being at takeoff and gear 2 being at 40mph+. If that's the case, I really need to find a CruiseOMatic for the extra gear. Would a CruiseOMatic bolt right in or would some mods me in order?

 

[MustangSix]

A cruisomatic won't help. Both trannies have the same 1:1 top gear, so your rpm will be the same at any given speed.

What kind of gear is in the rear end? You may want to switch that instead.

 

[flatford6]

Have you compared the manual low (L) gear speed with the first drive (D or Dr) speed. Some of those old Ford Automatics use a second gear start in drive, to get first gear you have to manually shift to Low and then to Drive. You can hold the trans in second gear by shifting from low to drive and then imediately after the trans shifts pull the selecter lever back to low while holding the throttle down. As to the top speed, lets review: Small engine, big heavy square non aerodynamic brick shaped, 50 year old car, possible speedo error because 50 year old speedo, wrong speedo gear or rear end ratio change. Other possible problems: punctured or non functional vacuum advance diaphragm, out of time, needs tune up, tired engine, slipping one way clutch in the torque converter. Good luck.

 

[Anonymous]

Trust me, I am really not concerned about speed off the line, or even at the top end for the most part. My main issue was that I am going to spend a lot of money to rebuild my engine and I wanted to make sure the tranny was acting like it's supposed to so I don't wreck the motor.

Yes, it will drop into the lowest gear in L and then go to 2nd and into 3rd at about 40mph, so it sems to be working properly.

In terms of the other possibilities, the distributor is new, timing was set to spec, it has all new tune-up items (and a Pertronix ignition) and the torque convertor is new.

Tired engine, small engine, giant non-aero brick? Absolutely!

The tag is missing on the rear end, so I'm going to have to figure out another way to find the gear ratio. I did a rough test with the speedo (wife driving beside me in her car) and it reads about 5mph high at 50 mph, so it's not too far off.

When I have the engine out for the reman, I'm going to go over the tranny just to make sure. I think this is just par for the course for the Custom "gas saver" edition - as they called it.

 

[flatford6]

A good way to check the rear end ratio is first to mark the driveshaft or rear u joint in relation to something on the third member. Then mark the position of the lowest part of ONE of the rear tires in relation to the ground. Then jack up ONLY that marked tire clear of the ground. With the transmission in neutral and emergency brake released, rotate the tire TWO turns and count the exact number of rotations of the driveshaft while doing so. The count of driveshaft rotations will be the exact ratio of the rear end to one. If you can't rotate one rear tire while the other one is on the ground and the trans is in neutral and emergency brake released, you lucked out, you have a positraction rear end.

 

[Colonel Flashman]

I have a 57 Custom with an automatic tranny. Now, from what I have read, the FordOMatic is a 2 speed transmission. When I am driving, I get a shift at around 38-42mph and that's it. By the time I am cruising at 65 or so, she's screaming pretty good. I really can't go much faster than 70. Granted, the engine is in need of a rebuild, but still...

Is that all you get with the 2-speed AT (one shift) or do I have a problem? I am assuming that it's correct with gear 1 being at takeoff and gear 2 being at 40mph+. If that's the case, I really need to find a CruiseOMatic for the extra gear. Would a CruiseOMatic bolt right in or would some mods me in order?

What you have is what is known as a Single Range 3 Speed Ford-o-Matic, which starts out in 2nd unless you drop it into Low or depress the throttle into kick-down for 1st gear, as apposed Dual Range 3 Speed F-o-M, which works almost the same as a Cruise-o-Matic.
Now what you can do is what the founder of Hone-o-Drive did.
Take an O.D. from a Manual Transmission an adapt it to your F-o-M, the same as he did for his '56 Ranchwagon, which he wrote an article about for "Hot Rod" magazine in July of '58.