rear end yoke

butch27 · January 24, 2006, 10:33:28 PM

O.K. I've got a 1940 Ford rear end ( closed drive) and was told by a very knowledgeable person that a P.T.O. yoke from a Ford tractor could be used to change to open-drive. Any ideas on which one will work?

enjenjo · January 24, 2006, 10:57:25 PM

I'll look in the Blue book, I picked one up friday at TSC.

BFS57 · January 25, 2006, 09:24:04 AM

Hello;
I just saw an article in one of my magazines on a new product that does just what you want.
Time out while I find it. (i'm at work now) Then I'll get back with much more info.
Bruce

Rochie · January 25, 2006, 12:25:10 PM

Quote from: "butch27"O.K. I've got a 1940 Ford rear end ( closed drive) and was told by a very knowledgeable person that a P.T.O. yoke from a Ford tractor could be used to change to open-drive. Any ideas on which one will work?

Butch,
I just finished the 40 conversion to open drive. I used the 6 spline coupler and a yoke from a 90/91 ford pickup. Bored the yoke and turned the coupler down to press fit inside the bored yoke. Welded the coupler to the yoke and drilled and tapped the pinion snout for 7/16ths fine thread for the bolt to hold the yoke to the pinion, cut a plate to hold the pinion seal and seal the cut down torque tube. It looks FACTORY. I't's 5.5 inches from the front of the flange where the torque tube mounts to the end of the yoke and there is a 3/32nds space between the end of the torque tube to the back side of the yoke. I have seen a number of conversions done where the yoke looks it is hanging on the end of a stick and I didn't want that look. The toughest part was drilling and tapping the pinion. Ol' Henry made them HARD. I ended up using full carbide drill bits and 4 taps to end up with good threads I also didn't want to spend the $300 or 400 US for the Rodworks conversion kit.
Wayne

enjenjo · January 25, 2006, 01:17:38 PM

Quote from: "Rochie"
Quote from: "butch27"O.K. I've got a 1940 Ford rear end ( closed drive) and was told by a very knowledgeable person that a P.T.O. yoke from a Ford tractor could be used to change to open-drive. Any ideas on which one will work?

Butch,
I just finished the 40 conversion to open drive. I used the 6 spline coupler and a yoke from a 90/91 ford pickup. Bored the yoke and turned the coupler down to press fit inside the bored yoke. Welded the coupler to the yoke and drilled and tapped the pinion snout for 7/16ths fine thread for the bolt to hold the yoke to the pinion, cut a plate to hold the pinion seal and seal the cut down torque tube. It looks FACTORY. I't's 5.5 inches from the front of the flange where the torque tube mounts to the end of the yoke and there is a 3/32nds space between the end of the torque tube to the back side of the yoke. I have seen a number of conversions done where the yoke looks it is hanging on the end of a stick and I didn't want that look. The toughest part was drilling and tapping the pinion. Ol' Henry made them HARD. I ended up using full carbide drill bits and 4 taps to end up with good threads I also didn't want to spend the $300 or 400 US for the Rodworks conversion kit.
Wayne

Got any pictures?

Rochie · January 25, 2006, 01:19:43 PM

Got any pictures?[/quote] Frank, I'll email some tonight for home OK

butch27 · January 25, 2006, 05:20:12 PM

Is that George C up there in Canada??

Rochie · January 25, 2006, 06:49:35 PM

Quote from: "butch27"Is that George C up there in Canada??

Nope, it's not George C. It's Wayne

zzebby · January 25, 2006, 09:46:07 PM

All the talk about converting to open driveline makes me question some of the old timers teachings. Now let me qualify this, some of these old timers are long underground, but I know that they still poke fun at my hot rod endeavors.
They told me that the hot setup to convert was to get all the parts off of a 42 to 48 or so pickup. They are already open drive so a simple conversion. The trucks were parallel leaf so the entire rear could not be swapped.
These old timers were well up on Lincoln big bendix brakes, zepher gears, F100 steering boxes and shock mounts and many other tricks that I didn't see in rod mags till decades later. They also had the stories about which Canadian made flatheads were the hot setup.
So I know that much of what they taught me is true, but I have no first hand experience on the truck open drive conversion. Anyone try it?

?

enjenjo · January 25, 2006, 10:20:34 PM

The truck parts work good. The only problem is finding one. What you can do, is remove the hubs, remove the side bells, install the car side bells, reinstall the hubs, and you have an open drive rear for a car.

The parts from TSC are 02-71041 this is an adapter from 1.125 6 spline to 1.375 6 spline, and 02-71935 which is a yoke that has provision for a 35N U joint. The adapter fits inside the yoke, and it will then fit the Ford pinion spline. There is some machine work involved, but this will get you the basics.

I like Rochie's method too.

The thought occurs there must be a yoke somewhere that would fit without machining.

Rochie · January 26, 2006, 08:45:54 AM

Quote from: "enjenjo"The truck parts work good. The only problem is finding one.
Enjenjo, there in lies the problem, around here anyway. There's not much left so you have to start thinking about alternatives. The truck parts do work well to convert to open drive and simply too. Just aren't readily found. I did this because I really like the look of a banjo under a car and figured the 40 differential I had (completely rebuilt)was worth trying. I know it's not a lot of money to buy the conversion, but there is so much more satisfaction in doing it yourself.
Wayne

GPster · January 26, 2006, 09:37:56 AM

I thought the bottom shaft in a "Quick Change" was just a jackshaft. Do they use different splines on each end of that jackshaft? Maybe the yoke for an open drive quick change would be what you need. Might be easier to find that way than for a '41 to '48 Ford truck. I'm surprised that the PTO didn't work out. I'd try to look specifically at Fordson tractors. I pulled a '40 Ford out of a feild one time specifally for the spindles and the front drums were gone. The farmer had changed them on his tractor so he could run truck tires/wheels on the front. I also let go of the rear end out of a '46 Ford coupe I was rodding because someone needed the pinion gear to replace one on an fence post auger on the back of his tractor. GPster

enjenjo · January 26, 2006, 10:08:28 AM

The open drive Quick changes used the 42 to 47 Pickup yoke, we're back to square one.

butch27 · January 26, 2006, 12:39:14 PM

O.K. : What is that company out in Idaho selling that is so special? Seems like really all the need is that yoke and you can make the rest of it. So what yoke are the using??

Rochie · January 26, 2006, 01:25:18 PM

Quote from: "butch27"O.K. : What is that company out in Idaho selling that is so special? Seems like really all the need is that yoke and you can make the rest of it. So what yoke are the using??

Butch, the company is http://www.hotrodworks.com/ They have built a complete kit consisting of a new pinion shaft, a yoke, and a cover. I used a yoke from a 90/91 ford 1/2 ton pickup. Bored the yoke and turned down the coupler for a press fit. The inside dia of the torque tube has a machined surface so you can refrence the cut from that for concentricity. The plate to hold the seal is also machined to fit the I.D. of the cut off end of the torque tube and the O.D. of the seal. A little gasket maker on the seal plate and slide them together.
Like I said in an earlier post the hardest thing to do is the drilling and tapping the pinion. Full carbide bits are the only thing I found to get into the end of the pinion.
If I wasn't a dumbass I would post a pic of the finisded conversion. Perhaps Enjenjo would do that for me.
Wayne