Technical Ford 4 speed OD transmission SMOD help!

It’s been forever since I posted, glad to be back!

So I’ve been Searching though all threads like mad and reading up. I have a Ford 3+1 OD transmission I want to swap into my 65 F100 w/302. Currently has a top loader 3sp that’s seen better days.

I was hoping this thing was a true 4sp top loader but looks like luck isn’t on my side.

I have a few questions - first I need a shifter. I understand hurst discontinued their shifter for this. Am I stuck crawling around a junk yard? Second, with this being a rather wide ratio should I be going to a rear end gear say 3.73...4.11.....? This truck will doubtfully ever see the thruway.



Thanks gents,
CM

 

If I'm not mistaken the actual shifer base is the same for both the standard 4 speed and the 3+1. The 3-4 arm is mounted upside down so you might need to tune up that rod so everything works. I doubt there's a total different shift unit for each.

 

the mounting holes look very different on my transmission. I wonder if it would still bolt up.

 

You may be able to redrill the mounting plate. If not, making the flat plate to mount the shifter is not hard at all.

 

I did it so.. so can you!

 

The Orion is pretty much tells you Is is a 3+1. A Hurst style shifter will bolt right up. I put one in my grandsons 390 powered F150 because it was the easiest way to a overdrive. I'm sure from the tires he went through it has not had an easy life. One thing do not do away with the full gasket under the top cover or it will loose oil out the breather. Make sure the front shift lever is pointed down oppsite of the other two.

 

Can’t help you on the shifter, but I ordered one of those transmissions new, behind a 300 six in my 79 Econoline. Unfortunately, I mistakenly omitted checking the box for the optional 3.50 axle ratio, so it arrived withe the new for 79 standard 2.75 or 2.79 ratio.

I struggled with poor highway performance for several years, then swapped in a swap meet 3.50:1 pumpkin.

The 3.50 was ideal. Plenty of around town zip for a large vehicle with a small engine, and I could pull small to moderate hills in fourth (overdrive) gear.

They were not robust transmissions, though. I replaced bearings and wore out the countershaft a couple of times in the 170k miles I owned it. Still ran great, but the trans needed another rebuild when the body dissolved from road salt immersion and I sold it.

 

Well come on man tell me more!!!

 

That’s what I may try I just wanted to verify before I dropped $700 on a new hurst

 

Should be lots of good used shifters out there. Easy to convert applications. Make a flat plate and if needed some shift rods. Save a bunch of money.

 

Hurst has discontinued most of their Ford toploader shifters, not just for these. Best bet will be a Mustang unit, but you'll probably have to build your own mounting bracket out of 1/2" steel plate. Keep in mind that most of Hurst's shifters are generic, the difference is in the mounting kit. Pay attention to which shift lever you buy. As the Wizzard says, the major difference is the 3/4 lever is flipped. The OEM linkage is rather sloppy from the factory due to too many rubber bushings (for NVH) but can be 'tuned up' for satisfactory operation.

This is their major flaw... These trans were a stop-gap measure, a quick-and-dirty way to get an overdrive. When in OD, the small countershaft bearings couldn't take moderate-to-heavy loads and will quickly fail. If you're planning on any towing or carrying loads, don't use OD, stay in '3rd' gear. I know quite a few guys who tried these in their trucks, this is a common problem. The aluminum-cased SROD was even worse for this. In a relatively light Hot Rod or if you don't put any extra load on the OD, they'll do fine.

As to changing the rear axle ratio, I'd be hesitant. The truck versions of these have a very low 1st gear (with a big jump to 2nd), going too low in the rear axle will turn 1st into a 'granny' low and be nearly useless. The car versions are better but fairly rare.

These were really intended for highway use, not around town. If the majority of your driving is town, stick with the three-speed. Those are nearly bulletproof, they do tend to develop noisy front bearings but it doesn't hurt them.

 

The bearing secret is not to run gearlube run 20w 50 motor oil

 

I would but the 3 speed is pretty spanked surprisingly. I think it’s got some synchro issues as it will randomly lock up between gears. Hence why going with the new trans

 

I put one in my '65 Gutlass and measured it out so the shifter would come through the factory hole. so I took a piece of 1/2" steel cut/chop/ drill/other things a guy does..yep shifter fits! Now make the shift rods do their thing. Yep perdy happy with me!!! NO REVERSE! Oh crap in my hat.....you have to drill out the back side of the mount so the shifter will move over to alow reverse

 

When you say it 'locks up', does it physically lock i.e. won't turn, or is it the linkage that locks (gets stuck in one gear, can't shift it). The latter is pretty common, by '65 ford's manual column shifters weren't very good. All you may need is a quality floor shifter for the three speed.

 

It locks up between shifts. It also leaks pretty good. I may use it for a different built but I’m set on removing it from this truck.

 

With all that said I think I’m going to just buy a complete new top loader 4 speed shifter and machine a new mounting bracket for it. But now it’s like there 47 thousand different models available for Ford top loaders.......

which kit would you guys go with?

 

Best bet will be to look here: http://www.davidkeetoploaders.com/tailhousingid.htm
… and see which one is the closest match to yours and order accordingly. Mustang/later Full size usually mounted the shifter further back compared to the other Fords. A lot of these kits have been discontinued AFAIK, the Mustang will probably be the best available choice. I wouldn't order a lever until you see where it comes up.

 

I actually tired to call his shop yesterday too for some advice but no one answered.

A buddy got me in contact with my local custom trans shop and they said they’ll have something that works or can custom make it so I’m going to shoot down there to talk to the owner today.
I’ll update this when I’m successful!

 

The picture of your trans is a cast iron overdrive Ford put out in the 70's and yours appears to be from a van or truck. Hurst was never a manufacture of a shifter for these. I have owned many of these and currently have one put back with a shifter. I could take pictures tomorrow of the shifter - not going to drag the trans out.. I also have had and have the next version TOD Ford supplied that is an aluminium case with a top shifter as found in later Jeeps. Ford use the later starting in the early 80's for just a few years. Here's a pic of the TOD - top loader over drive most always used in the trucks.........sorry my pic of the early 70's tranny does not have the shifter....

 

Alright well I got my hands on a used shifter. Still need to clean it up but it seems to be tight and operational.

 

Sent you a PM...

 

Replying to this old thread, but here is a graph I made comparing a close ratio 3 speed toploader the the car and truck overdrive toploaders. Since I had 1 of each.....

This is a speed/RPM chart for my 2.91 axle with dinky 14" tires.

 

Nice work - thanks for posting !

 

Would you think it's funny I just found the cast iron OD based on the top loader ? It was over by the early 9" - the shifter I have for it is from a van and really kinda tall as it was next to the van seat.

 

The cast iron 3+1 top loader only has the 65 up wide pattern. It sounds like your 65 has the 64 down narrow pattern. You can either drill the narrow pattern in your trans or use a 65 up windsor truck bellhousing with the wide pattern. As far as the shifter goes, I believe that the pad on your tail housing will accept a competition plus mount bracket. From there it is easy to mount up the 1-2 and reverse arm and rods and install the 3-4 arm upside down and massage the shift rod.

 

Your tail shaft although - it looks short for maybe a car - looks like the same as my long tail shaft I have. Wonder if a 65-73 top loader tail shaft will bolt up ?

 

I think the speedo gear hole is in a different location on the overdrive mainshaft. It is further forward line 2" I think.

This is a 3 speed Galaxie (long) mainshaft compared to an overdrive Granada mainshaft. I ended up having a longer driveshaft made and using the Granada tail housing.

 

Good info - thanks !

 

Stock overdrive truck (and possibly Econoline) shifter and linkage:







Note that this shifter mechanism attaches to the tailshaft as well as the upper bolts holding the extension housing to the main case.