Borg Warner Overdrive

M

Mike/Franklin

Member
I'm helping out some friends finishing assembly of a 32 Ford pickup. Owner/fabricator recently passed away and left about 80% assembled including a GM 3 speed with the Borg Warner already attached and drive shaft fit to the rear.
Question, can the overdrive be set as a pass through 1to 1 ratio?. And not use the overdrive feature. Nobody knows much about these units. They don't want to take it out of the driveline equation and have to redo mounts and driveshaft. Enough challenges already.

Thanks ML
 
There is a lever on the overdrive unit that is usually connected to a "lockout cable" mounted under the dash that is used to disable the overdrive unit under certain conditions. Fixing that lever in the forward position so it couldn't move would effectively achieve what you want. (This is for a Ford. I believe the GM unit would be very similar.)
 
Thank you, Tubman, I'll look for it Thursday night, our work night. We have a couple more of the same unit all cleaned up and ready up in the walk-up attic.
This fellow collected two and three of many of the components including probably 5 or six grills and other items.

ML
 
The Borg Warner R10 was used by GM and many other such as Chrysler, Nash, Packard, Studebaker, and Willys. The GM version was likely integrated with the Saginaw 3-speed in the early time frame but later ones could be Muncie or Saginaw. If locked out, it basically works like a regular 3-speed. If I had one, I'd use it as long as the internal parts like the planetary gearing, roller sprag clutch, and balk ring parts are all in good condition. The electric system can be set up to simplify it's operation similar to the way the model A torque tube R10 conversions were set up or it can have a full system like the auto manufacturers used. The addition of a separate high gear is a good addition. It's like having a semi-automatic transmission.

Use it like a three speed till ready to step up a gear if they want but I see no other reason to have it otherwise.
 
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^^ I agree. A properly operating O/D transmission is a very useful addition to these cars. Having one makes up for the shortage of T5's. Although at my age, I prefer the O/D because it requires less clutch manipulation. I hope the above is just a temporary step.
 
Rear end ratio and tire size need to be considered when deciding to use the OD or not. I agree that OD makes an older vehicle a pleasure to drive on the highway if set up correctly. I think a 3.70:1 or lower (higher numerically) is needed for OD unless there is a high torque engine used.
 
40cpe said:
Rear end ratio and tire size need to be considered when deciding to use the OD or not. I agree that OD makes an older vehicle a pleasure to drive on the highway if set up correctly. I think a 3.70:1 or lower (higher numerically) is needed for OD unless there is a high torque engine used.
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I think the highest gear ratio for early Fords is 3.25/1 and I believe that those are aftermarket. I would think that any modified engine at all would be able to pull that in a '32 Pickup. Of course, we don't know anything about the rear end (It could have been changed from the original banjo). The fact that they are running a GM 3 speed transmission suggests a small block Chevrolet under the hood. Even a stock 265 should be able to pull that fine.
 
Wow, this is really great info. Will help to make a decision on what to do. The rear is some sort of 10 bolt of unknown provenance. Thursday is our work night, and I'll get some decent photos of the truck itself and components.

Thanks again, ML
 
FoMoCo used the 3.9 rear axle ratio in the 1949 through 51 time frame on the Mercury cars and they worked really well. A taller gearing such as an automatic would have changed the intended operation on those cars. They were heavy and Ford wanted the car to be able to start out on a level surface in 2nd gear and then go into overdrive for basic around town cruising. This way, a person would only need the clutch at the stop signs. This was as close to an automatic as you could get until the Merc-O-Matic came out in mid 1951. For a light bodied car, it gives a 4th gear with an automatic kick down for passing, if wired like factory, so it's not a bad set up. They do need to be service checked more often for gear oil level if they start to seep. They have to have a good oil level in them to insure long service life. They are not a real heavy duty set up unless a person gets the T85 R11 type set up. Those can take a lot more torque if you like to hot rod around a bit. The T85 R11N with the high nickle casting can take a 390 FE with no problems.
 
Those overdrives work great, I ran them in a couple of vehicles. Using a toggle switch to operate the relay instead of the throttle kickdown makes them more useful. I used second gear overdrive quite often. Never had a problem with it.
 
Proartguy said:
Those overdrives work great, I ran them in a couple of vehicles. Using a toggle switch to operate the relay instead of the throttle kickdown makes them more useful. I used second gear overdrive quite often. Never had a problem with it.
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Wire it correctly and make sure it is working properly. You may decide to revisit your evaluation. Plus, it's easier to break something if they are not wired correctly.
 
They cannot be used in reverse so you need to install a switch on the transmission or manually lock it out when backing up.
 
Most of the R10 transmissions have an internal lock out that happens when you put the vehicle in reverse. The internal mechanism will block the pawl so it can't go into overdrive. When folks used the rear units for torque tube conversions then the cable has to be pulled to lock it out before shifting to reverse.
 
On the R10 OD installed in my '30 "A" If you left the OD knob down. (in) It would simply spin like being in neutral when one tried to reverse. No harm done.

You will wonder why you are not reversing and then aha, pull OD lever out. :)
 
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A thing that can happen if reversing with no lock out is that the balk ring may rotate the tab a bit to far the wrong way. There is a procedure to get it back in proper position. As long as a person is aware of that, they can look up the procedure in the manual. Most transmissions won't let it happen due the built in safely features. It's usually happens if somethings wrong or after some alteration has been made.
 
5 years of use and occasional backing in reverse with the knob down. No noise, no problems. It's like you are in a neutral. You just don't go anywhere. (Borg Warner R10.)
 
My '47 came with OEM transmission and a BW R10 installed just 8 inches forward of the differencial. As Proartguy mentioned, it was set up with toggle switch for operation and has the pull-out handle at dash for engagement. I was cautioned not to use the OD in first gear as it could damage it.
 
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