speedo gear

Clutch, transmission, rear axle

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shortbedCUSTOM
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speedo gear

Post by shortbedCUSTOM »

where can I get a new speedo gear? the one at the end of the speedo cable that is inserted into the tranny. the one I just pulled out is stripped. it's yellow with 18 teeth.

also, I'm assuming that it was the wrong one because my speedo showed 77mph eventhough I was travelling at 70mph. which one do you guys think I need?

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re: speedo gear

Post by FORDification »

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re: speedo gear

Post by flyboy2610 »

Your speedo is running 10% fast.
70 divided by 10 is 7. 70+7=77, which is what your speedo is showing.
And it's not wise for your speedo to be showing too much! :eek:
What you need is a speedo gear with 10% MORE teeth, so it turns slower by 10%
18 (number of current teeth) didvided by ten is 1.8. The closest you will get is a 20 tooth gear, so that's what you need.
I know NPD sells them, also.
http://www.nationalpartsdepot.com/
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re: speedo gear

Post by FORDification »

There's a guy on E-bay selling a few assorted speedo gears, but his auctions are due to end within the next few hours, so....

http://motors.search.ebay.com/_W0QQsass ... rtspackrat
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Re: re: speedo gear

Post by shortbedCUSTOM »

flyboy2610 wrote:Your speedo is running 10% fast.
70 divided by 10 is 7. 70+7=77, which is what your speedo is showing.
And it's not wise for your speedo to be showing too much! :eek:
What you need is a speedo gear with 10% MORE teeth, so it turns slower by 10%
18 (number of current teeth) didvided by ten is 1.8. The closest you will get is a 20 tooth gear, so that's what you need.
I know NPD sells them, also.
http://www.nationalpartsdepot.com/

thanks, that is what I thought. I'm ordering it first thing tomorrow morning. :)
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re: speedo gear

Post by shortbedCUSTOM »

ok, I have since swapped my four speed with a Tremec 5 speed. I installed the speedo gear that I had for the Tremec and now it shows 60mph when I'm traveling 70mph. which one do I need?
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re: speedo gear

Post by crazy larry »

I got a brand new one at my Ford dealer. who'd a thunk? and this was a couple of years ago, not twenty.....
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Re: re: speedo gear

Post by flyboy2610 »

shortbedCUSTOM wrote:ok, I have since swapped my four speed with a Tremec 5 speed. I installed the speedo gear that I had for the Tremec and now it shows 60mph when I'm traveling 70mph. which one do I need?
The current gear has 20 teeth, is that correct?
A gear with 20% fewer teeth would be a 16 tooth gear, and should show a reading of 72mph when you're doing 70. That's pretty close.
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re: speedo gear

Post by shortbedCUSTOM »

sorry, the one that is in there has 23 teeth.
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re: speedo gear

Post by flyboy2610 »

If you can get a 19 tooth gear for that it should show 69mph at a true speed of 70mph. That would be real close.
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