Author Topic: Speedometer Grear in Transmission  (Read 2954 times)

Offline dbolen3

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Speedometer Grear in Transmission
« on: August 27, 2016, 03:14:35 pm »
Does anyone know where to find charts on the little plastic speedo gear for a Turbo 400? I have put bigger tires on my truck plus changed my rear end gears so my speedometer is off by 10 - 15 mph

Offline SkinnyG

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Offline Captain Swampy

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Re: Speedometer Grear in Transmission
« Reply #2 on: August 27, 2016, 03:56:18 pm »
transmissioncenter.net    look for speedometer world
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline frotosride

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Re: Speedometer Grear in Transmission
« Reply #3 on: September 07, 2016, 07:50:17 pm »
Also if you call any major transmission supplier like TCI and tell them your gearing and tires size they will tell and sell you the appropriate drive and driven speedo gears.
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Offline hatzie

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Re: Speedometer Grear in Transmission
« Reply #4 on: September 08, 2016, 10:30:46 am »
I made a spreadsheet to calculate speedometer gears based on tire size and axle ratios.  If you have Excel or the Star Office derivatives (Open Office, or Libre Office).
http://forum.73-87chevytrucks.com/smforum/index.php?topic=32456.msg274736#msg274736
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