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Old 09-08-2008, 11:56 PM   #1
BoeJaker1976
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Speedo Calibration

Since i went with smaller tire, the speedo is reading faster than i actually am going. Who calibrates it? tranny shop? or is there some sort of formula that there is to change out the spider gear myself?

thanx
joe
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Old 09-09-2008, 03:25 AM   #2
BLE 'BURBAN
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Re: Speedo Calibration

Contact TCI TRANSMISSIONS. They used to have a chart on their website that would help to calculate the proper speedo gears needed for the transmission after entering all the needed data ( tire diameter, gear ratio, tranny type) they may still have it on their site but I didn't find it myself.
Good luck and happy wrenching!!!
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Old 09-09-2008, 03:49 AM   #3
MylilBowTie
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Re: Speedo Calibration

Its still up...

http://www.tciauto.com/Products/Tech...eedo_gears.asp
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Old 09-09-2008, 09:55 AM   #4
gchemist
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Re: Speedo Calibration

Try different size gear combos. Find a combo closests to a whole number. Your read will be off over or under by a little.
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Old 09-09-2008, 06:45 PM   #5
Captkaos
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Re: Speedo Calibration

http://www.73-87.com/7387garage/drivetrain/speedo.htm
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