11 - 37 gear set (3:36 ratio)

Kube

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I came upon a factory (matched set) of gears in my stash while looking for a set of 9-34's (3:78). The pinion remains in the gear case housing / center section. It (pinion) has ten splines and is stamped on end "11-37". That comes out to a ratio of 3:36.
I find no listing of this gear ratio in any of my books.
Am I simply blind or what?
 
Sounds like you have a pinion from a 3:54 gear set and a ring gear from a 4:11 gear set. I am like you, have never heard of such and do not find it either in the svc bul or parts books. There is always the possibility that a parts guy or even factory worker mispackaged the two.
 
Kube,I would count the teeth on the ring and pinion,I would not go by the stamping.Then if it does come out to 11-37 my thought is that you have a mix set of gears.EPW
 
Kube,I would count the teeth on the ring and pinion,I would not go by the stamping.Then if it does come out to 11-37 my thought is that you have a mix set of gears.EPW
I thought of that. The problem remains - these are a matched set. The pinion has factory stamping of "11-37". Also, I did count the teeth, a couple of times. It's an 11-37.
 
I have no proof of this but was told parts coming down the assy line that had minor defects were taken off the line and were destined to go into the parts stream for the dealers. No time on the line to fight a misdrilled attachment hole on a fender for example but a dealer shop would. Perhaps that gear "set" was identified as wrong and pulled from assembly stage, and instead of being scrapped, inadvertantly went into the parts stream. My guess is that what you have is indeed a mismatched set like jimTN suggests that got electropenciled as a real set. (you did find the matching number electropenciled on both gears?) I bet if you put that R&P together in a rear end they woudn't mesh correctly. You got a real oddball there no matter what!
 
Check and compare the ring gear you have with a 4:11 ring gear. Since the Ford banjo rear ends have only minor gasket adjustment, the distance from the middle of the gear teeth to the carrier bearing attachment (D in picture) will be quite a bit different between the two sets of correct gears sets.
 

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Mike, All matched sets have a matching serial number etched onto each gear. I'm not sure if they were individually lapped in, or whether the "serial" number represented a particular run and all having that number would mesh correctly. I don't recall seeing a set with the tooth count etched on, but check for the "serial" number.

By the way, if you'll notice, none of the gear sets divide equally, always with an infinite number. This is to insure that each tooth will engage an opposing tooth very infrequently, thereby reducing wear on all teeth.

I agree with duece roadster regarding NOS parts pulled from the assembly lines and packaged for use by dealers. I've heard that before, and have seen NOS parts that aren't quite to spec. Dealers, in turn, would set aside parts with defects beyond what they would normally encounter, and those are the NOS parts we find today that are considered pure gold!
 
Kube-

There may be some "factory truth" to a 3.36 rear axle. About a year ago I came across a Ford speedo gear marked "17." I know a "19" goes to a 3.78 axle, an "18" for a 3.54 axle but a "17"? I asked about the "17" and was told the "17" was used in conjunction with a limited factory special high speed rear axle. I have been unable to verify that the existence of such an axle ever occurred. However, maybe your 3.36 is the axle!

Tom
 

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The etched numbers that I have seen on gear sets have all been 4 digit numbers. Since Ford built more than 10,000 cars a year, it is possible that someone found a gear set with a matching number and either accidentlaly or on purpose put the mismatched sets together. If this is so, there is another set out there!!
 
Kube-

There may be some "factory truth" to a 3.36 rear axle. About a year ago I came across a Ford speedo gear marked "17." I know a "19" goes to a 3.78 axle, an "18" for a 3.54 axle but a "17"? I asked about the "17" and was told the "17" was used in conjunction with a limited factory special high speed rear axle. I have been unable to verify that the existence of such an axle ever occurred. However, maybe your 3.36 is the axle!

Tom
Tom, This I find very interesting. Your theory sounds the most plausible thus far. Thanks.
To others that have posted, to be CLEAR...
* This is a USED set that I'd removed years ago from a differential. So, we KNOW they mesh.
* The etched numbers match
* The "11-37" is not etched but STAMPED in to the end of the pinion gear. It is machine stamped. Precise and deep. Most certainly not hand stamped by any means.
 
If you check the speedometer gear charts in the Green Bible, it lists the 17 for certain truck axle ratios with specific tire diameter combinations. Even this series of charts for everything from cars to big trucks doesn't mention the 11-37 gear set. The No. 17 would work on a high speed gear set with car tires of a specific size though.

FoMoCo came up with a few different items for police use and they likely never made the chassis parts books unless they were in large quantity. Some stuff may never have been intended for the public. I've heard tales of a "high speed gear set" but I've never seen them before and assumed they were refering to 3.54:1.
 
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If you check the speedometer gear charts in the Green Bible, it lists the 17 for certain truck axle ratios with specific tire diameter combinations. Even this series of charts for everything from cars to big trucks doesn't mention the 11-37 gear set. The No. 17 would work on a high speed gear set with car tires of a specific size though.

FoMoCo came up with a few different items for police use and they likely never made the chassis parts books unless they were in large quantity. Some stuff may never have been intended for the public. I've heard tales of a "high speed gear set" but I've never seen them before and assumed they were refering to 3.54:1.

You are so very correct in that Ford made stuff that never made it in to books.
Researching to the depths I have and currently am has made me aware of things that will surprise the most pure '40 "affectionado" amongst us.
In regard to your mention of police cars... 1940 seemed to be a turning point in the companies policies.
In '39 there was a lot of talk about equipping cars specified for police & sheriff department consumption. In 1940 there was even more talk and some documentation that clearly shows how a police department went about getting said 'special equipment". Very hush - hush. However, in 1940 it happened without question. In 1941, it was no longer a 'secret" program but was officailly adopted by the company.
I am now more curious about this 3:36 set I have than ever before.
 
Oh, a used set. I made an error in assuming you were looking through your NOS stash!! It sounds like they are a real "set", and the number stamped in the end of the pinion sounds like OEM parts. That must have been stamped before the part was hardened. Do they have" FORD" on them anywhere? I think the aftermarket folks made gearsets back in the 40s and 50s. A long time ago I took apart a rear end that had I think 3.27s, (3.2something). Maybe Ford made those for the "flatlanders"! Pretty cool that you have those.
 
Oh, a used set. I made an error in assuming you were looking through your NOS stash!! It sounds like they are a real "set", and the number stamped in the end of the pinion sounds like OEM parts. That must have been stamped before the part was hardened. Do they have" FORD" on them anywhere? I think the aftermarket folks made gearsets back in the 40s and 50s. A long time ago I took apart a rear end that had I think 3.27s, (3.2something). Maybe Ford made those for the "flatlanders"! Pretty cool that you have those.
Deuce, You always seem to get me laughin!
No, not from the NOS stash (this time).
Yep, definitely stamped before hardening. I'll clean them up and see if I can find the script. However, I don't recall seeing any other ring / pinion sets scripted. Is my memory worse than I recall?
 
Oh, a used set. I made an error in assuming you were looking through your NOS stash!! It sounds like they are a real "set", and the number stamped in the end of the pinion sounds like OEM parts. That must have been stamped before the part was hardened. Do they have" FORD" on them anywhere? I think the aftermarket folks made gearsets back in the 40s and 50s. A long time ago I took apart a rear end that had I think 3.27s, (3.2something). Maybe Ford made those for the "flatlanders"! Pretty cool that you have those.

Hm, no 'flatlander' here ! But, I recently sold a ford with 3.27 rear gears and IMO is was darn good gearing..driving/gas mileage wise.
 
Kube-

There may be some "factory truth" to a 3.36 rear axle. About a year ago I came across a Ford speedo gear marked "17." I know a "19" goes to a 3.78 axle, an "18" for a 3.54 axle but a "17"? I asked about the "17" and was told the "17" was used in conjunction with a limited factory special high speed rear axle. I have been unable to verify that the existence of such an axle ever occurred. However, maybe your 3.36 is the axle!

Tom

Tom, the 17 tooth speedo gear could have been used on rural delivery vehicles equipped with larger than normal diameter production wheels and tires. Also, I believe the V8 era speedo housings and gears were carried over from the Model A. Bratton's Antique Auto carries a 17 tooth gear for a certain year model A with 3.54 rear gears and 21" tires.

http://www.brattons.com/prodtype.as...geHistory=cat&strKeywords=&strSearchCriteria=
 
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This is my impression on the gear set, Since the numbers are stamped on the set rather than electroetched, most likely this is an aftermarket set of gears from Getz or similar Co.. If you can get someone that has a selection of old auto motive speed catalogs to check the gear selections offered you may come up with the correct answer. I do not have an old Getz catalog in my library but a check of other catalog sources indicated that there was a 3.33 gear set offered for shoe box Ford rears so most likely that ratio was aslo offered for banjo style rears.
 
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