Speedometer gear for 3.08

Agnem

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Does anyone know what the correct color or tooth count is for a speedometer gear that would have been used with the 3.08 rear axle? I had a yellow one in there initially, and that was 10 MPH off (low) at 55. I don't know how many teeth it had... I think 18. I then went to a white one which was a 17 tooth gear. That one is 8 MPH off at 55. My dealer has indicated they don't think any other colors are available. If anybody actually has a 3.08 gear from a truck equipped with same, I'd love to aqcuire it. I'll also mention I'll probably need 2 of them, as I am looking for another 3.08 axle to install at this time as well.
 

iverger

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91F2504X4 posted this earlier, which only leaves you one more (16 teeth - Wine). Based on your results with the 18 and 17, it doesn't sound like 16 will be low enough though.

These colors refer to the cable end and not the gear on the tailshaft of your trans.

Manual Transmissions:

16-teeth-wine (C0DZ-A)

17-teeth-white (C3DZ-C)

18-teeth-yellow (C0DD-B)

19-teeth-pink (C0DZ-B)

20-teeth-black (C1DZ-A)

21-teeth-red (C4OZ-A)

Auto Transmissions:

16-teeth-blue (D0AZ-A)

17-teeth-green (C7SZ-A)

18-teeth-gray (C7SZ-B)

19-teeth-tan (C7VY-A)

20-teeth-orange (C8SZ-B)

21-teeth-purple (D0OZ-B)

The black gear on the tailshaft has 8 teeth I believe
 

david85

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I have a 16 tooth Blue driven gear (the one on the cable) and an 8 tooth drive gear on the tailshaft. Seems to read bang on.

When I ran the C6, I had an 7 tooth tailshaft gear and the speedo read about 10% low.

Got my blue gear from a local ford dealer for something like $8 and they even had to order it in.

Whats your second 3.08 rig gonna be?
 

Pino2234

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I have a similar issue except instead of 3.08s I have 3.55s with 37" tires. I have the lowest gear in my truck now (the 16 tooth) and I cant go lower. So I have to change the drive gear?

Where did you get the drive gear and Mel what did you end up doing to fix your problem?
 

david85

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PATC seems to carry them, but a ford dealer may also have it (thats where I got my blue driven gear).

In my case, the 7 tooth gear came with the transfer case along with the E4OD, so I didn't have to go looking for one.
 

tonkadoctor

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16 tooth is as low as it goes. That's what I had to run in my 3.08 conversion.

When I did it, from Ford they come 2 in a package and some dealers insist you have to buy both of them as they don't stock it.
 

Optikalillushun

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ya gunna have to change the drive gear in the tailshaft/transfer case. i might have a link for a lower gear...lemme check.

edit - i was wrong, its a 23 tooth gear and its made for a keep but can work.
 
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Pino2234

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I contacted Ford and they show 4 different types of an 8 tooth drive gear each of which are obsolete. I have to wait until tomorrow to get a hold of PATC.

Also since I last posted I found that with my 16 tooth driven gear if I get an 8 tooth drive gear for my transfer case my speedo should be right on.
 
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