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Discussion Starter · #1 ·
Was going to replace the cable on the speedo and discovered it wasn't the cable. The plastic gear on the end fell off so it's in the tail shaft housing somewhere. I don't think it's going to hurt anything in there but sure can't count the teeth on it when I can't get hold of it. Was wanting to put one in with more teeth (not sure how many more) to correct my speedo which is off by 15 mph. If my speedo says 80mph I'm actually going 65 mph.
Anyone have any idea what the normal number is for a 64 cruiso? It was a brownish red like maroon color.
Someone posted a link to some on here but can't remember what topic it was under.

Deb


<font size=-1>[ This Message was edited by: ShotRod64 on 11/8/06 1:09am ]</font>
 

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ShotRod64, since it's an automatic, you might be able to drop the pan and retrieve it. In any event you will have changed out the fluid. Steve
 

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Discussion Starter · #3 ·
I can remove the tail shaft housing I believe and get it. Just seems like a lot of trouble since I've been wanting to get one with more teeth to get my speedo more accurate anyway. Guess I could look at the bright side and call this a good thing.
One way to make me get it done instead of putting it off another year or two!
I saw some on ebay for automatics, 2 different teeth amounts. That might be the way to go to see which one might be closest to what I need.

Deb
 

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Deb,

Don't bother dropping the tail housing. That thing will only sit in there doing nothing forever....
Find out the # of teeth on the red by calling MACS or The Paddock or someone. They sell them by year and color I believe.. Tell them you're over by 15 mph and need the gear to correct it. They should be able to hook you up!
 

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I bought gears at the local Ford dealership for $7.75 each which was cheaper than those listed in other places. Plus, I didn't have to wait for shipping, etc. I was running a 16 tooth and was indicating approximately five miles over actual speed (70 on speedometer was actually 65) using a GPS for validation. I bought a 17,18, and 20 tooth and then swapped them out until I found the one that was most accurate. The 17 tooth was right on with the GPS. It's great to be able to trust the speedometer!
 

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Discussion Starter · #7 ·
A couple years ago I followed my husband in the truck and would watch the little speed trailers if they were parked along the road. At 32mph on the speedo I'm going 25 mph. At 70 I'm actually going 55 mph. We had the gps to play around with when we took the truck in to get a sleeve put in the head after blowing a plug and my speedo was dead. I was right on judging by sound for going 55 mph and 65 mph, of course the speedometer would have read 70 and 80 if it were working. Now after 2 yrs I finally got the exhaust hanger welded and new donut gaskets in so there goes the speed by ear til I get used to the quiet again. It's like driving with extra clogged ears or something now.

Next time we are in town I'll hit the dealer and see if they got some. Maybe i need the 18 or 20 since its off so far.
Here it's cheaper to order online than it is the gas to get to the parts store or dealer which are 30 miles from here.

Deb
 

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Deb, What gears did you put in the rear axle? Also the shop manual will tell you what gear goes for the rear axle ratio. I have a bunch of used gears and you can have the one you need.
 

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Discussion Starter · #9 ·
My speedo's been off since the day I hooked it back up a couple years ago. 3 to 1 ratio still. Only thing I've changed is tires and transmission. I don't even know how accurate it was eons ago but bet it was more than now. The original one was maroon and from I've seen that's 16 teeth. I'll have to call someone and see what they suggest to compensate for the 15 mph.
 

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Sorry, i dont have a link, but check out TCI, the transmission mfr. they have a formula that will figure for you the correct driven gear for your application. You have to have your rear gear ratio, tire size and the number of teeth on the driver gear inside your transmission. there are also other places that have this setup.
 

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Discussion Starter · #12 ·
There is a lot of different calculators out there to figure this out. So far the easiest one only covers the C6 or 4 spd CJ Mustang. I don't know the amount of teeth the driven? gear is in the trans which a lot of them want to know in order to calculate. This one is tire size and rear gear ratio which came out to be a 19 tooth gear needed. That might be off since it's a C6 and not an MX though.

http://www.428cobrajet.com/speedo-calc.html
 

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Discussion Starter · #13 ·
On 2006-11-07 22:21, 63ford406 wrote:
Deb, What gears did you put in the rear axle? Also the shop manual will tell you what gear goes for the rear axle ratio. I have a bunch of used gears and you can have the one you need.
I called Ford Racing and he said the gear I had/have is a 16 tooth but for a standard transmission. He said I'd probably need an 18 tooth gear which is grey to get close to the correct reading. You have a grey one?
Or if nothing else the other he mentioned was 17 teeth green one.


Deb
 
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