11 - 37 gear set (3:36 ratio)

[Kube]

Guys, I am sincerely appreciative of the thoughtful input. I have to admit, I am very intrigued by this "puzzle".
After reading Spadaro's post, I inspected the gear set even closer.
So now I can say with 100% certainty these are a FORD (oem) matched set. The pictures herein show the script on the ring gear as well as (180° opposite) some etching which reads #221, 11-37 ratio and L.008.
I have also attached a photo of the end of the pinion. That clearly shows the 11-37 stamped in.
I would really like to know the definitive answer to this one...Thanks!

 

[DICK SPADARO]

mystery continues, I checked a Republic set of replacement gears and they mark the set tooth count small /large like your picture but mine are marked in the band out side the differential bolt holes. I have 3.54" Ford" gear set and that is marked inside the bolts but is larger number/small number, neither of theses units is step machined on the back side like yours. The numbers you have supplied, to me, mean part #221, tooth counts and then L-.008 the back lash setting when installing gear set. Remember replacement part companies bought and reissued obsolete or excess OE inventory parts and private labeled them for resale. The tell tale is the 10 spline pinion shaft as that was pre 38.

 

[cmbrucew]

I recall that deucelover said that the 17 tooth speedometer gear was for a 3:25 ratio.

Bruce

Works good
Last long time

 

[Kube]

mystery continues, I checked a Republic set of replacement gears and they mark the set tooth count small /large like your picture but mine are marked in the band out side the differential bolt holes. I have 3.54" Ford" gear set and that is marked inside the bolts but is larger number/small number, neither of theses units is step machined on the back side like yours. The numbers you have supplied, to me, mean part #221, tooth counts and then L-.008 the back lash setting when installing gear set. Remember replacement part companies bought and reissued obsolete or excess OE inventory parts and private labeled them for resale. The tell tale is the 10 spline pinion shaft as that was pre 38.

Dick, Thanks for your input and apparent interest.
I realize obsolete stock was at time purchased and resold. However, if that were the case in this instance I would think someone (anyone) would have heard of this ratio before. Just "thinking out loud" here...

 

[Mart]

Ok, just as a sanity check - Mike, does a tooth count confirm 11 teeth on the pinion and 37 on the ring gear?

Mart.

 

[Kube]

Ok, just as a sanity check - Mike, does a tooth count confirm 11 teeth on the pinion and 37 on the ring gear?

Mart.

I so understand your post... went back and counted them both numerous times. Yep, 11 and 37.

 

[jimTN]

My 67 Honest Charley catalog has a 3:27 gear listed in the transmission ratio chart but not in the r&p listing, all r&p sets are 4+ for drags and high gear running on short round tracks.

 

[Mart]

Cool - I just thought there might be a slim chance it was a date code and not a tooth count.

3.36 is probably a pretty useable ratio for a non-od pre 41 (lets say) with a 239 or bigger motor. a 15/29 gearset would get it moving well.

I only say pre 41 because they are a bit lighter.

I'd use it in a heartbeat.

Mart.

 

[Lincoln]

This applies more to the comments about "a high-speed rear axle gear set" and the "17" marking on a speedometer gear ( the "turtle"). First off, Branch Service Letters in Jan. 1934 mentioned the "high-speed rear axle" which had a 3.54:1 gear ratio, which became an optional on the 1934. This used a "turtle" with the raised numbers of "11-39" on it. This combination would have applied to the Standard size Passenger tires used at the time. Then in May,1936 Ford removed the gear ratio numbers from the cap of the "turtle" and replaced them with a single number corresponding to the number of teeth on the speedometer gear (the depth of the teeth was also changed in order to use the "turtle" assembly with more than one rear axle gear ratio). Thus, the "11-39", above, would become "18". HENRY, no doubt, continued for awhile to use up existing stock of the older "turtles" before supplying the new ones.
Then sometime around July,1936 a "turtle" assembly 68-17270-B appeared bearing numbers "17" which, at the time, was to be used on the "11-39" or 3.545:1 rear axle, BUT only in conjunction with 6.00X18" or 7.00X16" Four or Six Ply tires ( it was noted that these tire sizes was listed only for informational purposes in the event they were used in other countries).
On Kube's axle, a search of Branch Letters up through late 1940 failed to uncover that a "11-39" rear axle was ever available, by Ford, in the U.S.A. Could it have come from Canada? Was there a "turtle" attached with numbers to the rear axle? Ford stamped the axle ratio on some center sections. Any numbers there?
Hope this helps.
Lincoln.

 

[Kube]

This applies more to the comments about "a high-speed rear axle gear set" and the "17" marking on a speedometer gear ( the "turtle"). First off, Branch Service Letters in Jan. 1934 mentioned the "high-speed rear axle" which had a 3.54:1 gear ratio, which became an optional on the 1934. This used a "turtle" with the raised numbers of "11-39" on it. This combination would have applied to the Standard size Passenger tires used at the time. Then in May,1936 Ford removed the gear ratio numbers from the cap of the "turtle" and replaced them with a single number corresponding to the number of teeth on the speedometer gear (the depth of the teeth was also changed in order to use the "turtle" assembly with more than one rear axle gear ratio). Thus, the "11-39", above, would become "18". HENRY, no doubt, continued for awhile to use up existing stock of the older "turtles" before supplying the new ones.
Then sometime around July,1936 a "turtle" assembly 68-17270-B appeared bearing numbers "17" which, at the time, was to be used on the "11-39" or 3.545:1 rear axle, BUT only in conjunction with 6.00X18" or 7.00X16" Four or Six Ply tires ( it was noted that these tire sizes was listed only for informational purposes in the event they were used in other countries).
On Kube's axle, a search of Branch Letters up through late 1940 failed to uncover that a "11-39" rear axle was ever available, by Ford, in the U.S.A. Could it have come from Canada? Was there a "turtle" attached with numbers to the rear axle? Ford stamped the axle ratio on some center sections. Any numbers there?
Hope this helps.
Lincoln.

Bob, You knowledge of these old Fords always amazes me.
The differential in question is a 11:37, NOT an 11:39.
There were NO numbers whatsoever stamped in the housing.
Kindest regards,
Mike