BB Tranny

[fordfixer]

Working with the Military Museum, they have an old military truck, that had a Model A engine installed with a BB tranny.
The tranny was removed with the engine for engine work. The tranny was opened up and found it full of water. Gears and such are shot.
Question is, is this just and AA tranny or something else. And then, where can one find parts?
Thanks for any info.

[Bob C]

The 4 speed gears were used from late 1929 until the early 1950's.
The AA case is different than the BB case.

[fordfixer]

So what is a BB tranny from?

[Bob C]

BB-7006 Case 1932-34

[Joe K]

Most of the internals are the same as the AA tranny. Recommended would be Ford's "Green Book" which will give you the blow-out of the transmission, and the part numbers of the various gears/bearings.

Many of this is available today from online sources, if not at your Ford dealership. (Back shelves.)

Ebay has the Green Book available on CD, also printed copies in various pricing/condition. Even Amazon has the Green Book. https://www.amazon.com/1928-1948-Gre...0-4513d670b6bc

I paid half of that for a Green Book on Ebay. Brand-spanking new.

Google terms are "Ford Green Book." The descriptive is universally understood.

Joe K

[Big hammer]

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Originally Posted by fordfixer

Working with the Military Museum, they have an old military truck, that had a Model A engine installed with a BB tranny.
The tranny was removed with the engine for engine work. The tranny was opened up and found it full of water. Gears and such are shot.
Question is, is this just and AA tranny or something else. And then, where can one find parts?
Thanks for any info.

I have a AA transmission that’s mostly complete and a later transmission that looks like the AA transmission, it’s yours if you want them. I’ll never use them, I’am in Vandalia Illinois, PM me if you can use them

[fordfixer]

Thanks for the info. I’ll have to check with them to get photos of it so I know for sure what I’ll need to find for them.

[fordfixer]

Can you text me at [email protected]
The museum is very interested in your offer.

[fordfixer]

Can you please contact me at [email protected]
The museum is interested in your offer.
Thank you.

[Big hammer]

I’ll send you a PM here on the Barm

[fordfixer]

Will the AA TRANS mount up to the BB BELL HOUSING? Just wondering if we can inter-change them.

[Fullraceflathead]

The clutch and brake pedals actually mount to the pin on the AA transmission housing.

[Joe K]

Originally Posted by Fullraceflathead

The clutch and brake pedals actually mount to the pin on the AA transmission housing.

Pin mounted pedals seems to have lasted all the way to 1948 (Green Book)


Joe K

[fordfixer]

Again thanks for the info.

[Reds34]

As far as I know, an AA transmission will bolt up to a BB bellhousing. You could take the pedal shaft out (or cut it off) if you have to.

Red

[john charlton]

Unlike the 3 speed transmission the 4 speed is not rain proof . When the cab roof fails rain water runs down the reverse guard rod and drips into the trans . When rescued my 31 AA the trans was full of water which in turn had migrated past seals into the back axle . Not a pretty sight !!!

John in Sunny Chandler AZ

[Joe K]

Originally Posted by john charlton

Unlike the 3 speed transmission the 4 speed is not rain proof . When the cab roof fails rain water runs down the reverse guard rod and drips into the trans . When rescued my 31 AA the trans was full of water which in turn had migrated past seals into the back axle . Not a pretty sight !!!
John in Sunny Chandler AZ

I've spoken on this in the "Resurrection AA" thread. Leave them out in the rain for a generation or two and they'll be full of water -which freezes here in New England and results in the "smile crack." The entire front wall of the transmission case is detached starting on one side and progressing to the other.

Perhaps you should have been that lucky to have the case cracked to let the water out?

These sorts of water affected transmissions are good for internal parts - possibly. And maybe why internal parts seem relatively plentiful.

Vince Falter describes another failure mode which has more to do with failure of internal needle bearings. But the effect is similar. I'll let Vince describe more accurately. https://www.fordgarage.com/pages/aatranscracks.htm


Joe K