AA ring and pinion gears.

[Tim McCormack]

I found an email from earlier this year from someone who was exploring the possibility of repopping the higher speed ring and pinion gearing for the AA's. Has anyone heard anymore about the project? What was the Outcome?

Merry Christmas!

Tim

[Chris Haynes]

A friend who is in to military stuff tells me that the 1930/'31 type split case timken rearend was used in a lot of WWII vehicles. He said they had higher gear ratios that the Fords used and that NOS ring & pinion sets show up at military vehicle swap meets.

[modeleh]

Alan Wernstrum in California had taken on the ring gear project awhile back, and the general consensus of the poll was to try and get 4.11 sets made. He is a busy guy and it's a complicated project, so it will take time. I seem to remember him saying in an email that the '32 and later Model BB rearends used different parts, so the ring and pinion project wouldn't be any good to those guys. Incidentally, I've become a BB owner (along with one AA), so the new gears wouldn't help me on that truck. Interesting information regarding the military parts, I wonder if they would be of the BB style though?
As a side note, I'm working on adapting a Hone-O-Drive overdrive to my '32 BB, to replace the short shaft behind the tranny. It is a synchromesh planetary overdrive (about 30%) that were made in the 60s and 70s. I will post more information on it later if it all works out.

[REM]

If I remember correctly the gears Alan was working on were for the worm drive rear axle.
The 30/31 bevel gears are obviously different from the earlier worm drive but I (thought) they were the same for a few years after 31. A source for higher speed gears for the bevel gear axle would be nice. The military source is an interesting option. I'd like to know more about them. Are some of them the same and what were they used in?

Richard

[Chris Haynes]

[quote="modeleh"]Alan Wernstrum in California had taken on the ring gear project awhile back, and the general consensus of the poll was to try and get 4.11 sets made. He is a busy guy and it's a complicated project, so it will take time. I seem to remember him saying in an email that the '32 and later Model BB rearends used different parts, so the ring and pinion project wouldn't be any good to those guys.


Hmmmmn,
I looked up the ring gear part number in my 1928-1932 parts book. They are listed as "6.6-1 BB-4207-A (was AA-4207-A), 5.14-1 BB-4207-B (was AA-4207-A)" This denotes that the 1930-1932 ring gears are the same.
The 1930/'31 pinion gears have different part numbers than the 1932's.
So it would appear that to supply all of the 1930-1934 trucks he would hove to make one ring gear and two different pinions.

WAIT!
I just called a friend who is up on rearends and he says that the AA pinion can be used in the BB differential if all the AA bearings and shims are used. Maybe this is the answer.

[Bob C]

The AA pinion is 1 3/8" and the BB is 1 1/2" so you need to make
some drive line changes.