Gear ratio

AA Ford Discussion Group relating to the repair and restoration of your AA Ford.
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Wickstop
Posts: 13
Joined: May 15th, 2014, 5:29 pm
Body Type: Unk
Model Year: 1928

Gear ratio

Post by Wickstop » August 29th, 2015, 9:33 am

Is it possible to chance the gear ratio on my 1928 AA with a worn drive rear end. Please advise

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spectria
Posts: 1874
Joined: May 15th, 2008, 9:53 pm
Body Type: Mail Truck, Stakebed
Model Year: 1931
Location: Quincy, Ca.

Re: Gear ratio

Post by spectria » August 29th, 2015, 11:39 am

Wickstop wrote:Is it possible to chance the gear ratio on my 1928 AA with a worn drive rear end. Please advise
Yes, you would need the set of worm and worm drive gears that you prefer.
Do you know what ratio you have now?
Dave in Quincy, Ca. I love Pics!!!! Post them All!!! :)
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KimVanOrder
Posts: 597
Joined: August 11th, 2013, 4:25 pm
Body Type: 82-A Platform
Model Year: 1928
Location: Hamilton, Mich.

Re: Gear ratio

Post by KimVanOrder » August 29th, 2015, 4:06 pm

Wickstop wrote:Is it possible to chance the gear ratio on my 1928 AA with a worn drive rear end. Please advise


Yes: The worm and Ring can be changed. The low speed, 7:25 to 1 ratio has an "A" stamped on the rear drivers side of the housing. The high speed is 5:17 to 1 with a "B" stamped on the housing. I am in the process of the same thing. (but still scratching my head if it is the right thing to do for my truck and it's history).

KVO
KVO
Dec. '28 AA

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1crosscut
Posts: 816
Joined: December 25th, 2010, 7:22 pm
Body Type: 82-A
Model Year: 1929
Location: Lincoln, NE

Re: Gear ratio

Post by 1crosscut » August 29th, 2015, 7:08 pm

KimVanOrder wrote:
Wickstop wrote:Is it possible to chance the gear ratio on my 1928 AA with a worn drive rear end. Please advise


Yes: The worm and Ring can be changed. The low speed, 7:25 to 1 ratio has an "A" stamped on the rear drivers side of the housing. The high speed is 5:17 to 1 with a "B" stamped on the housing. I am in the process of the same thing. (but still scratching my head if it is the right thing to do for my truck and it's history).

KVO
KVO - If I were you I wouldn't hesitate to switch out the gears in your rear end to a set of high speed gears. Everything is internal and no one will know it was done except you will go a bit faster. Mine was at one time a low speed rear end and the gears were switched out to high speed gears long before I got it.
The hard part is finding good high speed gears to make the switch.
------------
Dave

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blgitn
Posts: 192
Joined: July 6th, 2013, 6:36 am
Body Type: 275-A
Model Year: 1931
Location: West Point, VA 23181

Re: Gear ratio

Post by blgitn » August 30th, 2015, 5:00 am

Does anybody make other ratios?
I'd be interested in something like a 4:1, instead of searching for a warford.
R/ Roger.

Stakebed
Posts: 1187
Joined: June 14th, 2007, 7:29 pm
Body Type: Grainbox
Model Year: 1929
Location: Illinois

Re: Gear ratio

Post by Stakebed » August 30th, 2015, 2:54 pm

Not that i know of...warford is pretty much only way to knock ratio down even more...

Bob C
Posts: 1279
Joined: April 24th, 2003, 11:50 am
Body Type: Mail truck, Stake tr
Model Year: 1931
Location: SO CAL

Re: Gear ratio

Post by Bob C » August 30th, 2015, 5:30 pm

You could install a Mitchell overdrive or the 4-speed with 4th overdrive.

Bob
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User avatar
blgitn
Posts: 192
Joined: July 6th, 2013, 6:36 am
Body Type: 275-A
Model Year: 1931
Location: West Point, VA 23181

Re: Gear ratio

Post by blgitn » August 30th, 2015, 5:51 pm

Wow! I didn't know you could get a Mitchell for an AA. What ratios are available? Who's running one and what do you think?
R/ Roger.

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