bevel rear end

[macswoods]

what do I have ? Taking my 29 November AA rear axle apart . It has a later bevel gear axle in it. I found part of a tag
on one of the bolts.There is only about 1/2 of it left. Next to the bolt hole is a 4 and part of a (.) . Is not the tag for a high speed rear.(7.32). any idea ?

Mac..........

[Bob C]

I thought the high speed tags were 7-32 but maybe some were marked 5.14???

Bob

[njcar757]

According to Jim Schilds AA book, the bevel gear ratios were 6.6 to 1 and 5.14 to 1.
nick c

[macswoods]

yes I know what the gear ratios should be, but my question is what does the tag on my unit mean ? Mac.............

[Brady]

Mac: It could be "Inspector #4", just like 'Fruit of the Loom'... divide the number of ring gear teeth by the number of pinion gear teeth, and see if there could be some connection. Have a great new year-

[njcar757]

Looking at the Jim Schilds book page 19, the 28 to 29 rear axles assemblies had a part number like AA 4000 then followed by 2 letters to designate the gear ratio.

[Chris Haynes]

Your gear ratio is stamped on the gear of your speedometer drive. It is much easier to remove than than to split the case to count teeth on the ring and pinion.

[vtwinsideways]

Gotta be careful with the speedo gear method though too. Most will match and it's a good place to start, however Dads '29 had a 5.14:1 speedo drive gear and a 6.6:1 ring and pinion when we got it, so you can't be certainwith that method. (His junker '30 had a 6.6:1 rear and speedo driven gear, but no speedo drive gear on the drive shaft at all!) Luke

[russ]

Rather than take anything apart, maybe just count how many times you've got to rotate the driveshaft to get one full rotation of a rear wheel. That'll give ya yer ratio.

[macswoods]

that's how Neil told me how it is done. a little over 2 1/2 revs = high speed, 3 1/3 = low speed. Hold one wheel still, rotate wheel one rev to get the number of rev of the drive shaft, ,trans in high (4 th). Mac......

[spectria]

that's how Neil told me how it is done. a little over 2 1/2 revs = high speed, 3 1/3 = low speed. Hold one wheel still, rotate wheel one rev to get the number of rev of the drive shaft, ,trans in high (4 th). Mac......

I don't understand the trans being in gear at all, the driveshaft would not turn unless the clutch was held down. It should be in neutral.

Am I wrong?

[vtwinsideways]

Yep Dave, you're wrong. The idea is, you put the trans (and dual high if you have one) in high gear (this yields a 1:1 ratio on the 3 and 4 spd trans's), raise one wheel on the rear, mark the tire you raised and have one individual count the revolutions of the rear wheel, while the other individual turns the hand starter crank over 1 revolution. Luke

[markp213]

I too was confused until I realized you can't see the drive shaft due to the torque tube! Makes sense now! Thanks for the info.

[Neil Wilson]

Note that you count the engine turns to get the wheel to make one turn. Then double the count of engine turns. And, yes, the transmission must be in high to be a 1:1 ratio. And a dual high is direct drive with the peddle down in front.

If the axle is out of the truck, then you can see the drive shaft and you then turn one wheel, count the number of drive shaft turns and double that.

[spectria]

Yep Dave, you're wrong. The idea is, you put the trans (and dual high if you have one) in high gear (this yields a 1:1 ratio on the 3 and 4 spd trans's), raise one wheel on the rear, mark the tire you raised and have one individual count the revolutions of the rear wheel, while the other individual turns the starter crank over 1 revolution. Luke

Yep I was wrong...and right, I didn't see the instruction to turn THE ENGINE OVER and count the comparison...

I too forgot that in a normal AA assembled, you can't see the driveshaft in the torque tube, unless of course you have one like mine!!!

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DUH!