History BW Overdrive: Five Gears for the Price of Three!

OH! one A is wired that when the clutch is depressed it kicks OUT of od. the other A is wired that when od it stays ALL the time wnless lever is pulled to lock it out of od, with this tran i can take off with trans in od BUT if i forget to take it out of od BEFOR i put in reverse it will BREAK the od. also in mountains when in od and start down hill if i acelerate a little i can pull lever to get OUT of od and will save the brakes.

 

Does anyone know of a dashboard light with the word “Overdrive” in it so you know when overdrive is engaged?

 

What does the dash of your car look like? Most older cars didn't have a legend for indicator lights, they just had a light, and you had to know what it means. So any kind of old light assembly would work.

The light would not tell you exactly when it's engaged, only that the solenoid is getting power, eh?

There are conditions where the solenoid gets power, but you're still in normal drive. Such as when you are accelerating and up to governor speed, but have not let off the gas yet. Or when you kickdown, and let off the gas part way, but still kicked down. Under these conditions the light would be on, you be in direct drive, not overdrive.

 

I have a BW OD in my 55 Chevy. I´d never thought I´d love it that much. The 55 has a 235 and originally came with 4.11 gears. I put in a 3.55 pumpkin and love it even more now. Cruising at 85 mph is comfortable.
I have a second OD trans as a spare, just in case. Have you guys ever rebuilt one? Straight forward or many hoops to jump?
I had a solenoid fail last year and was glad I could steal one off my spare trans. Seems like new ones are prettey pricey at about 300$. I´m still looking for a spare one.

 

They're not too hard to overhaul, the trick is having a parts unit so you can have the parts to repair it. Planetary pinion rollers can go bad, the cam can get pitted, there are some funky snap rings, and of course you need the proper size rubber band to hold the rollers on, when you reassemble it.

 

Thanks Jim!...I do have a 55 shop manual, that should help too when the time comes.... do you know of anyone making parts for these ? Core transmissions ain´t that easy to come by in my neck of the wood

 

I think you can still get gaskets and the seals, and maybe the bearing and bushing, but as for hard parts, no.

 

Parts for these have been hard/impossible to find for years, and most of what you will find will be for Fords/Mercs as they sold the majority of them. These guys... http://www.vanpeltsales.com/FH_web/trans-partsprices-BW-ODparts.htm … have the best selection I've seen but it's all Ford-oriented. Some parts are generic to all overdrive units, some will fit 'other' makes, but it's a crapshoot. While some new parts are available, a good number are only available as used so supply can be very iffy.

 

E-Bay is actually your friend when it comes to these OD parts and pieces. There is apparently a company making some new solenoids and governors, along with relays and wiring, and the prices seem reasonable considering what used ones start out for. I am Butch/56sedandelivery.

 

The hardest part of overhauling mine many years ago was discovering the access to the hidden circlip under the "frost plug".

 

yeah, it's tricky! The manual is a big help, but they still leave a few things for you to figure out on your own.

 

When you're freewheeling down a mountain, can you pull the cable and get OUT of OD? Or does it blow up?

 

It's easier to push the cable in, than to pull it out, when you're moving. But as mentioned above, give it some gas, it will let you pull the cable out. It will also shift into OD and not freewheel, once you get above governor speed (about 30-35 mph), but by then you might be going too fast to make that hairpin turn.

It can get exciting.

 

R10 for Chevy. They did have them hooked to the older non sychro'd first 3 spd and the later syncho'd 3 spd. At least around here it's really hard to find a later GM o/d, then the early GM o/d and you can trip over Fords.

 

Is it possible to do away with the electrics and build a reliable mechanical setup?
Engineering the cables and levers is within the realm of most of us here. What am I missing?
I recall someone attempting to do just that....cannot remember which forum I saw it on.
Worn out brain cells ya know.....

 

The OD works with a solenoid, and the electrics are not very complicated...and make life better if you get them working. You can replace the normal relay with a horn relay, and the kickdown switch with a microswitch or other push button mounted on the dash, if you don't want to find original electric parts.

It might be possible to replace the solenoid with a mechanical device, but it would need to be spring loaded and do some fancy stuff.

Lots of guys seem to wire the solenoid to a switch, but if you do that, you need to be sure to remember about it all the time when you're driving. There are some funny things with reverse, etc.

 

My 56 Chevy Belair two door sedan was a factory OD car and still has the cable installed. My original build planned for a 327 and a Muncie and I have the Muncie rebuilt and ready to go in when I get back to working on that project. But the thought of the overdrive is constantly in the back of my mind. If I could ever find an overdrive unit reasonable enough I will change my plans and install one in my '56.

 

The car I am speaking of is my wife’s off topic 70 MGB with overdrive. It is a standard four speed but overdrive can be engaged in either third or fourth. The switch is built into the wiper stalk. You push in the clutch then pull the wiper stalk towards you giving you effectively a six speed. These trannys are pretty easy to come up with and are stout and reliable. I will be making a wood dash for it eventually, and the light I have in mind could be from any make or model. I often thought a MGB engine and tranny would make a nice drivetrain for a model A roadster or similar size car. The price would be right and all the parts are readily available.

 

I am planning on putting an OD into my '51 Ford. I have two complete transmissions, so I think I'm good there. I was lucky enough to save a good relay from a '50 I scrapped, but the rest of the parts were junk. I found the lockout cable, the kick-down switch, and a wiring harness quite easily, and they weren't priced crazy either (they save that for solenoids). I believe I got the kick-down switch and wiring harness from one of the early Ford parts dealers, but IIRC, I had to go to a Studebaker parts guy to get the lockout cable.

 

Cole-Hersee makes a switch that I think you can use for the switch under the gas pedal. Part number CH-90043-07. I have never used one, but I THINK it will work. It’s kinda of an odd functioning switch!






Bones

 

I have a BW unit in my Model A Roadster. Built into the torque tube. I love it, cable lever comes up the gear shift and also the toggle switch is on the same bracket as the cable. Nowadays everyone wants the Mitchell units because they're 25% instead of the Borg's 33% but my roadster does fine with the high gears. Going up a 6% grade you just flip the toggle off and blip the throttle and you're back in direct. The "A" is an otherwise pretty stock banger. B motor with pressure and a downdraft 81.

 

You guys are scaring the shit out of me.
My 50 shoebox has the BW overdrive but is as yet an unknown entity.
My bro said it worked when he put the car in storage(30 years ago).
I'm kind of building(fixing) the car so I can take it on highway trips so I don't have to spin my o/t to 3200rpm
to keep up with my pals.
I'm a couple weeks away from firing it up at which time I will test the OD.
I'll start crossing my fingers now.

 

If the overdrive worked well when the car was put away, it should be okay now, assuming the car wasn't put into very damp storage, in which case there would be much worse problems than a faulty overdrive transmission.

 

Don't sweat it. Yet.

Sent from my Trimline

 

I tried one of the reproduction solenoids but I just did not have much luck with it. I bought a NOS Delco solenoid, as long as the shaft length is the same they should interchange. I had to grind two flat spots on the ball end of the shaft to match my Mercury transmission but then the od worked reliably with that one. I used a generic aftermarket 5 pin relay and a dash mount push pull switch, works wonderfully.

 

If I'm not mistaken the Model A setups are usually made from a 60's Rambler R-10 overdrive as they were flanged at the back for a torque tube. I have a couple Rambler units if someone is inclined to build one. Let me know. They'd need rebuilding but the housings are the hard part to find.

 

I have a ‘65 Ford Country Sedan (Galaxie Wagon) that has a 390/3sp OD, R-11 unit. I bought the barn find car solely on the trans. I grew up watching Dad row our ‘55 Chev wagon, 265/3sp OD, while mom had a cute Black 59 Rambler American flat head 6, 3sp OD. So I knew how nice they were on the hiway and in town. Mom really missed the trans when dad bought her a new ‘67 Mustang, 289/3sp.

I jumped at the chance to buy the Country Sedan which had sat since 1981 on an Idaho farm. My dad and I cleaned it up, made it road worthy. I’d drive it cross country tomorrow. Even behind the gas hog 390, the wagon knocks down 18mpg on the hiway.

Ford put them in cars until ‘67, and in F150s until the mid 70s. Great transmission!

 

I just love my '53 Mercury with three on the tree and O/D. Just got back from a little road trip and the 125 hp flatty cruises nicely and very comfortably at 65-75 in O/D. Drive it like a four speed, keep the lock out disengaged, take off in first, shift to second before 27 mph, accelerate through 45, ease of the gas (I just push in the clutch as if shifting but you don't have to) drops into O/D then just pull up to highway speed and shit to third. Wonderful car to drive.

 

I bought a '63 Galaxie 4-door as a cheap temporary driver this year. It has a 289 w/ 3-speed + OD. Kind of an unusual setup, as I'm not used to seeing OD behind a 289. It's been surprisingly fun to drive around. Has also been converted to a switch to activate OD. It's funny to take non-car people (usually co-workers) for a ride in it and try to explain the column shift and overdrive. They've never seen anything like it before and are just baffled by the whole thing.

 

Love that Mercury. My favorite Henry product/year.

Ben