AA 4 speed in 1928 roadster pickup

[Fullraceflathead]

Does the special U joint bolt onto the output shaft on the AA 4 speed transmission? I have mine apart and it was not bolted. The U joint is just kind of floating on the output splines.

[katy]

Does the output shaft have the threaded hole in it?
See: https://www.snydersantiqueauto.com/p...9685&cat=41815

[1930artdeco]

I 'think' it sits on the spines. At least the 4 speed that I have looks like the back end of the regular 3 spd. I have the short shaft and it looks like the torque tube of regular car set up. But I could be wrong...

Mike

[Flathead]

Is the output shaft threaded? If so I would bolt it on .

[RoadsterJohn]

Pretty sure it floats on the splines

[Fullraceflathead]

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There is some damage on the metal bell housing that fits over the U joint and the torque tube rides against. That’s why I’m asking the question because it looks like if it was bolted to the output shaft it wouldn’t be able to float and rub against that bell shaped U joint housing.

[Fullraceflathead]

Some photos
I guess it’s possible maybe they exploded a U joint sometime in the past, the current U joint is in very good condition.

[Fullraceflathead]

Originally Posted by katy

Does the output shaft have the threaded hole in it?
See: https://www.snydersantiqueauto.com/p...9685&cat=41815

I purchased this and have the 3/8x24 1” long bolt in case I do need to bolt it to the output shaft like the 3 speed is.

[Fullraceflathead]

I’ve even thought maybe the bolt came loose and that’s what did the damage to that housing but there was nothing inside when I took everything apart not even metal chips. I think that damage may be previous damage from this truck past. There was plenty of grease in there when I disassembled it and the U joint pulled right off the splines with my hand it was not frozen or rusted in place but it does seem like it should be bolted on like the three speed transmission U joint is. I wish I had a definite answer though I would hate to put this all together and then find out I got a tear it all back apart.

[Fullraceflathead]

I’ve driven this truck probably 1500 miles or so and it’s never giving me any noise the reason I removed the rear end assembly is because I sheared the clutch release fork pin inside the bell housing.

[1955cj5]

Mine has the threaded hole and was bolted together.

Here is a picture. 4 speed on the left.

Mine was certainly cobbled together from an AA donor, but it does have the unique special u-joint.

I could go over to storage later and get more pictures if you like.

[Fullraceflathead]

Thank you 1955cj5, I was gonna private message you because I do remember you removing your AA 4 speed. I think I'll go ahead and bolt mine together then as it seems like that was the original Ford plan.
It doesn’t make sense to me for the three speed to be bolted and the four-speed not to be bolted since it’s basically the same exact U joint angle and coupling used on the model A.
The setup on the big AA truck may be different but this is an actual Model A that was converted probably in ‘30 or ‘31 as the casting date on the transmission is 11-29.
Yes this transmission has the Special 1” thin cast iron bearing retainer Not the more common AA 1 3/8” thick bearing retainer casting.

[1955cj5]

I took a few pictures.

The washer is pretty thick, 5/32", and is 1 5/16" in diameter.

You can see the marks where it was pulled tight against the splines on the u-joint.

Bolt threaded portion is 13/16", by 3/8" fine thread. Overall length is 1 3/16".

And also the inner shield. Perhaps yours was damaged by the original bolt having poked through one of the holes after it came loose....must have made quite a racket!!

[Fullraceflathead]

Thank you for the pictures 1955cj5.
I think you may be right. I think my truck had a hard life at some point before I owned it.
I was able to find a good bell cover in my parts stash to use.
I removed the output shaft bearing retainer casting to clean and measure the actual thickness and unfortunately I was wrong in my original thinking. It’s actually the standard AA one that’s 1.375 thick. I still need the correct 1” thick one but may never find one. I’ll reassemble everything using what I have to work with for now. I may machine one out of aluminum at some point in the future as I have a Mill and Lathe and the print.
I’m surprised everything fit with the extra 3/8” but the rear spring is taking up the mismatch. I’m sure the extra pressure on the torque tube area that mates with the U joint bell is under more stress but ok as long as I keep things well greased. This truck has been this way since 1960 or so.