What Overdrive Transmission is this?

Bud

Well-known member
I have a friend with a Model A that has the transmission shown in the pictures. I am not familiar with it. He says it is a 4 speed with overdrive. If you look, it is mated to a Model A bell housing, not a AA bell housing (I think). I don't believe it is an F150 transmission.
Does anyone know what this transmission is? Any comments regarding its reliability or any other observations?
Thanks,
Bud
 

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It's a T170 or RTS, see link below. I did my own conversion using this transmission last year. The difference is night and day. The ability to make quick synchronized shifts maximizes your hp enough so you can drive in normal traffic. Being able to downshift saves on your mechanical breaks.

The OD gives you more top speed while lowering you limited RPM's and prolongs engine life.

http://www.fordgarage.com/pages/TremecT170FT.htm#:~:text=The 1984-87 Ford F,known as a T170FT RTS.
 
It's a T170 or RTS, see link below. I did my own conversion using this transmission last year. The difference is night and day. The ability to make quick synchronized shifts maximizes your hp enough so you can drive in normal traffic. Being able to downshift saves on your mechanical breaks.

The OD gives you more top speed while lowering you limited RPM's and prolongs engine life.

http://www.fordgarage.com/pages/TremecT170FT.htm#:~:text=The 1984-87 Ford F,known as a T170FT RTS.

Did you have to shorten the torque tube?
 
It is a F150 Transmission 4 speed w/OD. The pictured installation uses a Model A bellhousing. They are excellent transmissions. I did my own conversion using a AA bellhousing. Have driven it several thousand miles on cross country road trips with no trouble. The AA bell housing eliminates the need to cut the center crossmember plus the gear shift lever is very near the original location. Three OD ratios are available. They are getting hard to find as well as replacement parts.
 
I took a look and the torque tube was cut and re-welded about a foot in front of the pinion flange at the rear axle. About how much is the height difference between a AA housing and the A housing?
 
I took a look and the torque tube was cut and re-welded about a foot in front of the pinion flange at the rear axle. About how much is the height difference between a AA housing and the A housing?

That means they shortened the rear radius rods and drive shaft also. Can your see where the radius rods were welded?

I don't know the difference between a AA housing and the A housing is.
 
It looks to me like they cut off the front parts of the radius rods and welded them there.
So is this transmission basically an orphan where one can't service it if something goes wrong?
 
No not an orphan,just got to look a little harder to get what you need for them. Great overdrive trans for an A. We have two in the family both with the AA bellhousings (1/2" shorter) and love them.
 
No not an orphan,just got to look a little harder to get what you need for them. Great overdrive trans for an A. We have two in the family both with the AA bellhousings (1/2" shorter) and love them.

So Phil, Someone cut ½" off the torque tube, drive shaft and radius rod so they could use the Model A bell instead of using the AA bell? A lot of work. I have heard that if you use the AA bell you have to rig up clutch and brake pedal mounts? True.

Anyway seems like a nice setup.
 
Ruth, the Torque tube, Radius Rods and Drive Shaft are shortened approximately 2 1/4"
(? Memory escapes me) when using a AA bell housing. The AA bell housing is approximately 2" SHORTER (front to rear)than a Model A bell housing. Brackets for the Brake and Clutch Pedal Shaft and the E-Brake lever must be fabricated. The clutch assembly is Model A. Throwout bearing is AA with a sleeve over it (made from A trans. throwout collar sleeve.) Clutch disk is from F150. Model A Gear Shift Lever is welded to the F150 lever.

I have never installed one using a Model A bell housing.
 
Here are a couple of pictures of the clutch and brake bracket.
 

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The cut on the torque tube /driveshaft is more than the 1/2". the trans is a longer in length than the A that"s why you have to shorting things up. The AA bellhousing makes it so that you do not have to cut the crossmember of the frame and places the gearshift closer to the orig. location. But you do need to make a pedal mount.
 
The cut on the torque tube /driveshaft is more than the 1/2". the trans is a longer in length than the A that"s why you have to shorting things up. The AA bellhousing makes it so that you do not have to cut the crossmember of the frame and places the gearshift closer to the orig. location. But you do need to make a pedal mount.

Thanks MAG and Phil. OK, I see. I took your statement as there was ½" difference between the AA and A bell.

So help me out. If there is only a difference of ½" between an AA ans A bell, and the F-150 trans is longer than the Model A, do you still have to cut the torque tube, drive shaft and radius rod when using the AA bell?

I am just trying to get it straight for my own knowledge. I have a Mitchell and don't plan on changing.

Thanks.
 
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Thanks MAG and Phil. OK, I see. I took your statement as there was ½" difference between the AA and A bell.

So help me out. If there is only a difference of ½" between an AA ans A bell, and the F-150 trans is longer than the Model A, do you still have to cut the torque tube, drive shaft and radius rod when using the AA bell?

Thanks.

Yes
 
Yes, you still have to cut the Torque tube, Drive shaft and Radias Rods.The length of the Torque Tube is critical to within 1/32 of and inch. If too long or too short will not mate to the trans correctly. Radias Rods are teh same problem If to long or too sshor will n ot fit to be boss on the
Torque Tube.
 
I am just finishing the installation of an F150 4 speed in my Model A. Gary Bernard from Fort Worth, Texas did mine. We used the original bell housing, and he shortened the torque tube and drive shaft. He then modified the brake cross shaft. I did not have to modifiy the crossmember at all, and all pedals work as original. I will shorten the radius rods. Shifter will be about 3 to 4 inches further back, but will clear the seat easily and looks like it was supposed to be there. Very easy install, and I am looking for to trying everything out.
 
Thank you all for your comments! This was very helpful in understanding what I was looking at.
 
I went back and looked and the car has had the front of the frame cross member cut to clear the transmission.
 
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