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Could only find them at Steeda and they want just as much to ship. Anywhere else?
Which one do you need (what gears and tire size do you have)? I probably have one at the shop.
 

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It is an all stock '97 t-bird and I guess I need the Purple one.
Mine is a stock Bird with 215/70-R15 tires and 3.27 gears which should be the same as your ride. If I'm not mistaken, I have the gray gear. If yours is all stock with the transmission that came in the car, you will need the same.

I'll look for one in the morning, but as Chris said, might be quicker to grab one from the stealership on your way to/from work.
 

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Just want to make sure I understand you post here http://forums.tccoa.com/showthread.php?t=132130

I have a '98 F-150, with 4r70w, and I'm installing an Eaton True Trac diff. and uping the gears from the stock 3:55 to 3:73....

So with that, I need the purple gear (21 tooth, Purple (D0OZ-17271-B) which is for 3:27s ??
Is there another speedo gear for the truck??? My dealership can't find it and the trucks going to the shop this week......all I want to do is keep my speedometer accurate.......and I've tried searching the internet and all I find are gears listed for mustangs or older tranys,

Thanx..........
 

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1997 Thunderbird 4.6, 1998 Mark VIII LSC
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Stupid question then. The universal consensus here seems to have been the 21 tooth gear for 3.73s, which is what I bought and installed. However my tires (26.1" height) are approximately 770 revs/mile, which would work out to a 20.1 (20) tooth gear. Also for a stock height tire of 26.8" and 3.73s, that would also be a 19.6 (20) tooth gear; both numbers differ from the sticky. If I wanted to be right on with the 21 tooth gear, I would need over 800 revs/mile meaning a tire only 25 inches tall, whereas to be right on with a 20 tooth gear I'd need a tire that is 26.4 inches tall, much closer to both stock and what I have now. What am I missing?

Also you can get your speedo gears from RobertP. He'll get you one for about $11 shipped.
 

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Stupid question then. The universal consensus here seems to have been the 21 tooth gear for 3.73s, which is what I bought and installed. However my tires (26.1" height) are approximately 770 revs/mile, which would work out to a 20.1 (20) tooth gear. Also for a stock height tire of 26.8" and 3.73s, that would also be a 19.6 (20) tooth gear; both numbers differ from the sticky. If I wanted to be right on with the 21 tooth gear, I would need over 800 revs/mile meaning a tire only 25 inches tall, whereas to be right on with a 20 tooth gear I'd need a tire that is 26.4 inches tall, much closer to both stock and what I have now. What am I missing?

Also you can get your speedo gears from RobertP. He'll get you one for about $11 shipped.
It's all about variance. A tire height calculator shows your tires (255/45R17) to have a revs/mile value of 770, but the manufacturer claims it is 790. Using that value, it works out to 20.6, or the 21-tooth gear.
 
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