A vs AA Transmission

[1955cj5]

This a has been in the family a long time...I recently brought it home from storage at my brothers place.

It had the AA transmission since before we owned it (1962).

In a week and a half I have learned to dislike the AA transmission and would like to replace it with the proper A transmission.

I have no idea what else may have been altered when the AA transmission was installed.

Does this look like a typical A bell housing off a 29 or 30?(it has a 1930 engine)

That's about 7 1/2" across the bellhousing casting where the transmission bolts up..

What else should I look for?

Randy

[Bob C]

The 4-speed bell housing will not work with the 3-speed. What don't
you like about the 4-speed, it should shift like the 3-speed except for
the super low first gear just start in 2nd.

Bob

[hardtimes]

Hey Randy,
I'm kind of with Bob here, in that, if you start out in second gear that should / would suit better for driving. Then if truck has a load and/or you wish to creep along, you then have the creep first gear!
It must have been 'the thing' to put AA 4 speed trans in the '29 truck. I have an AA 4 speed and an A trans ..BOTH out of '29 ford trucks. Do you have the 'lockout' lever on your shifter stick ? My AA 4 speed has that feature.

[1955cj5]

Yes I have the lockout.....

First gear is a creeper for sure!

It just does not want to shift into second from a standstill...first and reverse no problem.....Otherwise it shifts fine. It is noisy in all gears...

One thing is I have 140 wt oil in there....the 600w is on order and I will change it out when it arrives.

Maybe i can get used to it..but it just does not seem to be very well installed...the rear mount just sits on top of the crossmember, and the shift tower sticks up higher in the cab....

[harleytoprock]

You have an AA bellhousing. The AA bellhousing is shorter in length and desirable to those who want to do a F150 or T5 transmission conversion. The AA housings are worth $150. to $250. The A bellhousing is what must be used if going back to A 3 speed and is worth less than half as much. If you are interested, I have a A bellhousing and A 3 speed transmission available, . Venders sell a Mitchel transmission which is a stock A 3 speed built with synchronized 2nd and 3rd gears and they offer different gear ratios. A stock A 3 speed core is required to be turned in.

[fiddlybits]

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Why does it look like the engine is only sitting on the mounts, not bolted to them? (And has been shimmed up)

just so it is clear....600W is not 600 weght. 600W is the product name. Its weight is somewhere around 175 i think. Like creamy peanut butter left in the sun.

145 will lube but you may have to delay your double clutch a bit as the gears wont slow down as fast.

[oldbike99]

From the second picture, the bell housing is not even bolted to the rear engine mount. A bit of work is in order, but it is usually that way after eighty plus years!

[1955cj5]

This old truck has so many things missing or poorly installed or broken...86 years of hard use and minimal maintenance..

And yes...the bell housing is only bolted to the mount on the left side....the right side is what you see....

unfortunately it looks like the bolts have been broken off flush with the bell housing surface...

I have ordered new motor mount rubber pads and bolts, and maybe just maybe I can get what's left of the bellhousing bolts out.

Does that rear transmission mount sitting on the crossmember look normal for an AA conversion?

Let me see how the 600w oil works for me..and a local owner mentioned that since it had been sitting so long the flywheel face and pressure plate may have some corrosion. When I was in high school we used to drive this truck around..i don't remember it being so difficult to get into second from a stop....but I'm pretty sure my brother put 90wt gear oil in it since then....

I got a ride in a local owner's beautiful 29 Fordor....it's the only other model A I've ever been in! What a treat!

[Bob C]

If the pin in the top of the transmission tower is worn it can make
it hard to get into some gears, look at the video Fullraceflathead made
on repairing this. https://www.youtube.com/playlist?lis...E4m50cDoDpBOJh
It also help to let the clutch out just a little to get the gears to mesh.

Bob

[40 Deluxe]

Bobc, it sounds like his clutch may be dragging so the gears are grinding when he tries for second. Since first is a low, low gear, it's turning slow enough that it can be slipped into first even though the gears are still turning.
Might try putting into second before starting the engine, and then downshifting as you come to a stop so you're in second at the stop sign, ready to go without any grinding!

[hardtimes]

Hey Randy,
Wow, if that situation is only half bolted in, no wonder you are having trouble with it !
There must be a ton of unnecessary stress put on the entire driveline when torque is applied...if not lined up and bolted down as per original. Wonder something hasn't busted...or maybe it has.
The 140 wt is good for your trans/rear.
I'd first try to get it all checked out for damage/cracks, then bolted down properly and adjust clutch. It sounds amazing that you can shift it at all what with the different stresses being unsecured will cause.

[1955cj5]

I'm going to do my best to set it right...

I was wondering if maybe the rear transmission mount sitting on top of that crossmemeber wasn't forcing the front of the engine to be too low..the front engine mount looks a little low, but i have nothing to gauge it by...i don't have a hand crank but a socket extension seems to line up with the crank hole OK....

The brake cross tube does not touch the transmission, but it's pretty close...I was able to get the speedo drive gear off to check it and remove the mangled speedo cable...

Lots of issues here for sure.....

[1955cj5]

I watched Fullraceflathead's video as posted above....My shift lever is pretty loose, 3" sided to side measured at the shift lever just under the knob...and there is some rotational movement also..

I guess I better put that on the list

[Fullraceflathead]

My 1928 Roadster Pickup has the 4 Speed AA Transmission in it.
Mine does not have a rear mount at all. The mounts are on both sides of the Engine and the one at the front of the Engine.
The bracket you have on your Transmission looks like it is not original.

[1955cj5]

Thanks for that.....when I get the rear motor mounts repaired I'll see how tough it is to get that mount off...

Today I took the shift lever out. Mine has the screw-on cap and only one locating pin.

The pin looked OK and was a snug fit in the tower, but as you can see the lever ball is pretty well worn. And down inside the shift rails are also pretty worn....a little here and a little there, and soon it's just plain loose!

I also replaced the manifold gasket, studs, washers and nuts (it had bolts with regular flat washers), fuel shutoff valve and the carb bowl gasket. I'm hopeful there will be no more seeping fuel. I also set the float level up a bit..1 3/32" measured from the gasket flange to the top of the float...

[Fullraceflathead]

Yes the slot area is very worn. Mine was almost the same. I made my pin oversize in diameter and a little longer so it went into the unworn area of the slot.
The Pin is available but to really fix the slop issues I would have the worn areas of the slot welded up. It doesn't take much of a weld bead to build up the worn areas.
Your AA is the later version with the threaded shifter cap, that's a good thing. The caps are available new old stock. They don't wear much though.
Be very careful that pin doesn't drop into the transmission. If it does you'll have to either use a magnet to retrieve it or remove the PTO cover and get it out, unless your lucky enough to have it pass out the drain plug hole while draining the oil.
The pin was missing in mine and some one used a stove bolt in it's place. It had so much slop I could move the shifter 7" or more in all directions even when it was in gear.

[1955cj5]

I have a mig welder...it's 120v but it ought to do the trick....but there are other fish to fry first..

Also the tension spring on the shift lever was almost flat, nearly just a spacer...

[1955cj5]

Originally Posted by Fullraceflathead

My 1928 Roadster Pickup has the 4 Speed AA Transmission in it.
Mine does not have a rear mount at all. The mounts are on both sides of the Engine and the one at the front of the Engine.
The bracket you have on your Transmission looks like it is not original.

I gave the mounting bracket a closer look and I see that it is just welded to the u-joint housing.....

They needed it for a reason.....more will be revealed....

[Fullraceflathead]

Let me take a few photos of mine so you can see how mine is set up.

[Bob C]

The bearing retainer on the back of your transmission looks
like for a 32 or maybe later.

Bob

[Fullraceflathead]

You should see a casting date on the Transmission case. Mine is on the drivers side near the Top. Mine was cast 2-13-31.
Since yours has the threaded style shifter cap it is the later one. I'm not sure when they changed. I do know the shifter cap that is held in by the Pins is considered the early AA Trans. I believe they came out at the very end of 1929 and only in AA Trucks. They were a common Dealer retrofit into Model A's especially in the Pickups. They are the Beefier Truck Transmission, very Heavy Duty. They made them well into the 1950's the gears that is. The cases changed often.

[1955cj5]

could this be a 32 AA transmission? How would I tell?

[Bob C]

It's not a 32 trans, the 32 and later have no provision for the clutch
and brake pedals.

Bob

[1955cj5]

I found a little cast tag that reads...7--3.. could that be July of 33, or is that the wrong tag? There is a mark next to it that looks a little like a @ but about 5/8" diameter..

[Fullraceflathead]

Here is a photo of mine.

[1955cj5]

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Thanks for the picture....nothing there on my casing though. I see at the bottom on your case is the "AA 7000"...I found that on the passenger side of my case, about 1/2 way down, with the number "4" below it......

Still looking!

[1955cj5]

Here is the tag that is on my transmission..

[roblesterjr04]

Originally Posted by Bob C

The 4-speed bell housing will not work with the 3-speed. What don't
you like about the 4-speed, it should shift like the 3-speed except for
the super low first gear just start in 2nd.

Bob

It looks like he's got the older AA trans with the 3 speeds + hi/lo foot lever. Maybe if he puts it in high and leaves in there.

[1955cj5]

There is no foot lever..but I've seen pictures...but where would the foot lever have connected to the transmission? Did they use the PTO access? The battery is right there on the driver side...so no room now....

Thanks!

[Tom Wesenberg]

Originally Posted by 1955cj5

There is no foot lever..but I've seen pictures...but where would the foot lever have connected to the transmission? Did they use the PTO access? The battery is right there on the driver side...so no room now....

Thanks!

There would be a HI-LO tranny in place of the intermediate shaft, right behind the main tranny.

[Bob C]

He's got a Model A not an AA.

Bob

[Tom Wesenberg]

Originally Posted by Bob C

He's got a Model A not an AA.

Bob

OK, he mentioned the PTO access, so I assumed he had a truck with a 4 speed.

[Bob C]

Originally Posted by Tom Wesenberg

OK, he mentioned the PTO access, so I assumed he had a truck with a 4 speed.

He has a pickup with a truck 4-speed.

Bob

[1955cj5]

You remember the motor mount with the 5/16 plate on top and no bolts to the flywheel housing?

New parts came today and the mounts have been replaced and the bolts installed...

The bottom bolt was just missing, the top bolt was broken almost flush with the case so I Dremeled a groove in the stub and took it out with a screwdriver....easier said than done but it is done..finally...

[Fullraceflathead]

That looks good!

[Tom Wesenberg]

Originally Posted by 1955cj5

You remember the motor mount with the 5/16 plate on top and no bolts to the flywheel housing?

New parts came today and the mounts have been replaced and the bolts installed...

The bottom bolt was just missing, the top bolt was broken almost flush with the case so I Dremeled a groove in the stub and took it out with a screwdriver....easier said than done but it is done..finally...

Notice the gap at the bottom of the motor mount in the first picture. That shows why original mounts are better than float a motor mounts.

It looks like at least one of the bell housing bolts has a rounded head, rather than a flat head. It might have been switch with another engine bolt of the same size. The side water inlet has rounded head bolts, and the timing cover does also.

[Neil Wilson]

The 4-speed transmission rear bearing retainer should look like the one in the photo below. This is for the AA chassis. The A chassis used the same retainer except it was about 1/8" less in thickness.

The bearing retainer shown in the 1955cj5 photos is not the A chassis part. Also, there was not support used as shown in one of the 1955cj5 photos.

[Bob C]

Vince has information and pictures of the parts to install the
4-speed in the Model A on his web site. http://www.fordgarage.com/pages/aafourspeedachassis.htm

Bob

[1955cj5]

Thanks for the photos and information....

Right now the rear bearing retainer is a mystery...I don't thing it looks like the AA retainer but I'll go look more closely....

And today I think the support that is hanging on the crossmember will come out.....

There is pressure on it so it is supporting weight....I just hope the transmission does not rest on the brake cross shaft once the support is removed.....

[1955cj5]

Originally Posted by Fullraceflathead

You should see a casting date on the Transmission case. Mine is on the drivers side near the Top. Mine was cast 2-13-31.
Since yours has the threaded style shifter cap it is the later one. I'm not sure when they changed. I do know the shifter cap that is held in by the Pins is considered the early AA Trans. I believe they came out at the very end of 1929 and only in AA Trucks. They were a common Dealer retrofit into Model A's especially in the Pickups. They are the Beefier Truck Transmission, very Heavy Duty. They made them well into the 1950's the gears that is. The cases changed often.

I finally found the casting date, under a layer of grime! 2-12-31....the day before yours! But its on the shift tower and not on the case....and so far there isn't one on the case itself..different foundry?

Been mulling changing back to a 3-speed....were there different torque tube lengths? Measured a 1930 today and it was 49 3/16 from the back edge of the clam shell to the front of the flange at the differential.....mine measured 49/1/2"....does that sound right, or has the tube been altered?

Randy

[1955cj5]

And one more thing.....

Anyone know what the oil capacity is for the AA transmission?

I've searched and searched and haven't found anything...

I've read that the A is one pint..

I've put two quarts in the AA and it's still not quite full, and now I'm out of oil but it's nearly full as I can see it through the filler...

It sure shifts better with te 600w and it's quieter too...

Randy

[1955cj5]

Originally Posted by 1955cj5

And one more thing.....

Anyone know what the oil capacity is for the AA transmission?

I've searched and searched and haven't found anything...

I've read that the A is one pint..

I've put two quarts in the AA and it's still not quite full, and now I'm out of oil but it's nearly full as I can see it through the filler...

It sure shifts better with te 600w and it's quieter too...

Randy

I found the answer....I had to sign up over at thee aa-ford forum so I could search..

The AA transmission holds 6 pints...3 quarts.....considerably more than the A transmission.....

[1955cj5]

I have solved the shifting problem. The pressure plate was out of adjustment and as a result the clutch linkage was way out of whack...

Shifts fine now...

http://www.fordbarn.com/forum/showthread.php?t=172037

[1955cj5]

I thought I'd post a couple of pictures of the AA and A bell housings side by side....about 1 7/8" height difference...

[1955cj5]

I learned a couple more things about the AA vs the A transmission...at least on my installation..

Mine has a 32 or 33 BB rear transmission bearing retainer...BB-5089-A..i found one on ebay...

And the bolt spacing on the u-joint clamshell is 2 7/8" vs the 2 3/4" spacing on the A clamshell with evenly spaced holes...

[1955cj5]

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Don't know..it's in there..I didn't put it there....the upper ears have been broken off...

Remember I have a 4-speed, which must be AA because the pedals still mount on the transmission case...

I looked at a fellow's 30 ccpu the other day, he has a 4 speed...the rear bearing retainer is very different...

But this is a picture of mine...

[1955cj5]

I recently bought a copy of the Service Bulletins. While paging through I noticed this subtle difference between the 4-speed and 3-speed on page 509...

And sure enough my old AA clutch shaft was offset, but the replacement was an A shaft and so though most of my shifting problems with the 4-speed had been resolved with new bearings, clutch disc and pressure plate, this just created a new problem....

AA 4-speed shaft on the right...

4-speed is gone now and the 3-speed works great.

[Mike V. Florida]

He might be in the market for your AA tranny if you are thinking about selling.

http://www.fordbarn.com/forum/showthread.php?t=190358