Shoebox Driving with Overdrive

Smitty

Well-known member
Hi All,

Looking to get an idea of what to expect in driving a 50 Ford with overdrive. I have been reading up on how it works. The "free wheeling" part concerns me a bit. Does not seem like a good idea to be without a sound link between the engine and rear end. I have a Mitchell Overdrive in my Model A and I love it but this Borg Warner in a Shoebox seems to be a different animal...
Is it safe or should I shy away from this type of transmission?


https://fordification.com/tech/overdrive.htm


Steve
 
The Borg Warner unit has a good reputation of service. The free wheeling should not affect normal driving if the unit is in good repair. If you drive in hilly country, it is a good idea to disengage the overdrive to allow engine braking for safety.
 
It does coast longer but they do slow down. It doesn't engine brake well unless the overdrive is locked out. It's a lot like an automatic transmission.
 
under normal operation, the free wheeling only occurs below 25ish mph. This is a low speed giving time to correct if necessary. BTW, some (most , all?) new cars incorporate coasting to enhance fuel economy. When you drive a correctly operating BW overdrive your fears will disappear.
 
What would happen if you were to say hit the brakes at 40. Article had also mentioned that below 28mph free wheeling would be in play and you would be able to shift into first gear? That could be kind of cool. They must work if they were in use for many years by many car companies.
In climbing hills would you want to pull out the cable or would the "kick-down switch" take that function?
Steve
 
In order to pull the cable, the transmission has to be in direct drive (out of overdrive), so you would have to hit the kick down switch to pull the cable if you are running in OD. Hitting the brakes at 40 would be just like any standard shift car. Be very careful shifting into low while rolling. If there is any drag in the transmission you could chip a gear.
 
My first car in high school was a '51 Ford with overdrive. Even as a complete novice, I had no trouble at all once my old man explained a few basic rules, the most important of which is mentioned above.

You may be overthinking this.
 
BTW, some (most , all?) new cars incorporate coasting to enhance fuel economy.


Do you have any references as to which new cars have this "coasting" feature? I have never heard of such a feature. Seems like it would cause all kinds of rear end collisions as the Sams and Sallys are preoccupied on their phones! Plus, burned out brakes in the mountains.
 
I have had 3 Fords with BW overdrive. Two flathead V8s & a 6 cylinder. They are WONDERFUL & the "free wheeling is NOT an issue. Love the kick down. kina like a passing gear, even in 2nd gear. A real fun trans to drive.
 
Do you have any references as to which new cars have this "coasting" feature? I have never heard of such a feature. Seems like it would cause all kinds of rear end collisions as the Sams and Sallys are preoccupied on their phones! Plus, burned out brakes in the mountains.

Specifically, we have a Genesis that has 5 selectable driving modes. One is "ECO" that allows the car to coast when the accelerator is released. "Coasting" appears on the dash when coasting is active. Most newer cars have high gearing and smaller engines that makes engine braking barely detectable anyway.
 
Almost all automatic transmissions have a freewheeling clutch built in. Just use the brakes to slow.

If you are at speeds less than 23 mph, it drops out of overdrive. To downshift the unsynchroed 1st, you have to match Engine speed to the speed of the Car before attempting a shift. Double clutching may help some.
 
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I love the overdrive in my 51. For a little extra engine breaking once the OD is engaged, or extra acceleration if you don’t want to floor it for a kick down, simply downshift into second.
 
You'll love the free wheeling when you discover not needing the clutch to shift gears. Also use emergency brake when parking and/or lock out the overdrive. It will roll in gear.
 
Not if you park in reverse gear.

Yep, that was a lesson I learned even before getting my license. "Always shift into reverse when parking." Even with non-overdrive transmission cars. Back then, automatics were relatively rare. And if you had a Chrysler product with Fluid Drive, you HAD to use the parking brake every time so it didn't roll away.
Also, we were taught that when parking downhill, turn your wheels toward the curb and away from the curb when parking uphill. Otherwise, your poor old worn out engine didn't have enough compression to hold the car on a hill and it would slowly roll away.
 
Early Hydra-Matics didn't have a "Park" position either. I was instructed to always put the car in reverse when parking it, I habit I still have to this day.

IIRC, you were supposed to use "Reverse" in the early Hydra-Matics when parking as well.
 
Early Hydra-Matics didn't have a "Park" position either. I was instructed to always put the car in reverse when parking it, I habit I still have to this day.

IIRC, you were supposed to use "Reverse" in the early Hydra-Matics when parking as well.

Some early ('56 or so?) Hydramatics had what I call "German engineering". When put in Reverse and the engine switched off, a spring applied the parking pawl. When the engine was started and shifted out of Reverse, line pressure released the parking pawl. (Needless complexity!)
 
Good points here, got my license in the mid 60's and would always put the trans in reverse and if on a hill point the wheels to the curb.
Also: my 50 is running on 12volts, guessing I am going to need to install a 12 volt solenoid..
S
 
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