Ford 3 speed manual with overdrive in EB

[mebco09]

Planning my next project-

Has anyone ever put a Ford 3 speed overdrive transmission (manual) in an EB? I think these transmissions were available in 1977-78. (RUG-BP)

My goal is to attempt to keep the column shift manual, but have that overdrive gear.

I am not sure how you would make the OD work, I have seen Chevys with overdrive handles under the dash attached to cables.

Anyone tried this setup? Is there another way to do it?

 

[Viperwolf1]

I would connect the 1-2 and 3-OD levers to the column shifter and have a separate lever for reverse. BTW, I just saw one of these in the wrecking yard 2 days ago. Don't know if short output shafts are available for them any more.

 

[jamesroney]

Everything that Viperwolf said…and this:

A transmission with 4 progressive forward gears is called a 4 speed. If you try to find a mainshaft for a 3 speed, it will confuse everybody.

His column shift idea is clever. I would be inclined to use an air cylinder to engage reverse. The factory shift detents will prevent engaging two gears at once…and you wouldn't have to cut a hole in the floor.

 

[Broncobowsher]

4-speed column shifts did exist. I remember reading about them in the owner's manual for a 76 Plymouth Fury (and know a friend who drove one once). '84 Econoline also had a column shift 4-speed if I recall correctly.

While not something you will find in North America, 5-speed column shifts have been built. A co-worker was talking about one he had while in Australia.

As for running a 4-speed (that is what a 3-speed with overdrive is) will take 3 shift levers. Trying to run that with a 2-gate column shift will leave you without reverse. Getting that 3rd lever to activate the reverse, not going to find a way to add that to the existing column. So a stand alone shifter, it has been done. Air shifter is an interesting idea. I have done it for a kickdown on a C6.

But I will really suggest you check that interlock a little more. I've seen several transmissions that interlock on adjacent gates but not against distant gates. NP435 can shift low and reverse at the same time as long as the 3-4 gate is in neutral. (435 reverse is to the right of the 3-4 gate). Reverse interlock check that the 3-4 gate is in neutral, 1-2 interlock checks the 3-4 gate is in neutral. But 1-2 gate has no check with the reverse gate.

 

[73azbronco]

Man you could have 5 shift levers on the floor with a twin stick in there, no one would ever steal it.

 

[mebco09]

Everything that Viperwolf said…and this:

A transmission with 4 progressive forward gears is called a 4 speed. If you try to find a mainshaft for a 3 speed, it will confuse everybody.

His column shift idea is clever. I would be inclined to use an air cylinder to engage reverse. The factory shift detents will prevent engaging two gears at once…and you wouldn't have to cut a hole in the floor.

Yes, I figured the one I was looking at was technically a "4 speed", but instead of a direct 4th, it was a .85 OD. Looks just like a toploader 4sp.

What I was really thinking of was this: My great Uncle had a 1963 Impala that had a gearbox at the rear of the transmission. Maybe an "eaton overdrive" if I recall (?). You pulled a cable under the dash and that engaged the OD. I think it would reduce all gears, so you had "high" gear in every gear, like a two speed rear end. Not sure if it would work off the back of a transfer case though.

 

[Jdgephar]

http://www.davidkeetoploaders.com/imposters.htm

Sent from my SM-G981U using Tapatalk

 

[Jdgephar]

You can probably use the 4 speed toploader shifter, assuming they can still be found. But thats a floor shifter instead of column. I have the 4 spd in my 72.

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[nvrstuk]

I ran a 3 spd w/OD back in the late '80's. I ran it with a Hurst 4 speed floor linkage.

My .02 on the tranny? Didn't like it at all. I spent time & money attempting to get more mpg and with a 302 I didn't get any increase. Maybe a big cubic inch engine it would have helped some. Same worthless gear splits, same no low first gear, no mpg increase. For me it didn't work out at all.

 

[Broncobowsher]

That's why most just do a NP435 4-speed. Same horrible gear splits, but at least you get a nice granny gear out of it.

 

[mebco09]

That's why most just do a NP435 4-speed. Same horrible gear splits, but at least you get a nice granny gear out of it.

Call me weird, but I like column shifts. My Dad's 67 is on the tree. I did mine with a AX15, and now that it is going back together, I wish I did a column shift.

I may just do a 3 speed on the next one and keep it on the column.

 

[AC932]

That overdrive on your Uncle's impala was (probably) a Borg Warner R10/R11. They were in a ton of cars in the 40s-60s.

Pulling the cable actually disengages the overdrive; it automatically engages when you let off the gas over 28 mph. Automatically disengages when you smack the gas or go under 28 mph. It also freewheels below 28mph, so you lose engine braking below that speed (and also don't have to use the clutch to shift).

FYI the overdrive ratio on an R10 is 0.63. The R11 is a heavier dutier version, but harder to find. R10's are probably fine for Broncos with mild power plants.

There was an adapter made to bolt an R10 to the back of the D20. It's called a Rancho, there's a thread on here about it. Very hard to find the adapter; the R10's are pretty common though. If you go that route, Van Pelt Sales has all the parts needed to rebuild the R10 units.

Be cool if someone would start making those adapters new. You also need a few electronic components, and your driveshaft will get even shorter. Also have to change the output shaft yoke.