Another speedo thread

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rwljpl

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Rich
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1987
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1500
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383
so I got my speedometer working but it’s off — it underreads by 15-20 mph. I have an np203 from a 1977 but the cab, including gagues, is a 1985. I have been told I have 3.73 gearing (front and rear) but I have not chrcked gearing myself. I have 33” tires. The speedometer gear is all metal. See pic. Can I do anything to fix this and get a more accurate reading on the speedometer?
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Matt69olds

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There is a speedo gear calibration chart on TCI frequently asked question page. You need to know tire diameter (not the size) and the exact gear ratio. Then they can tell you what teas you need to get your speedo accurate
 

Kim Burke

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Talked to this guy today about another speedo cable issue and my truck is way off calibration too. He would be a great guy to call for some info. Talked to me like he had all day and seemed very level headed and knowledgeable.


Speedometer Repair Services


449 E Kiowa St, Colorado Springs, Colorado 80903, United States

(719) 632-3165



[email protected]
 

Standi

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Looks like I have an issue too. Called Rusty at Speedo Service. Really nice guy with lots of knowledge. Highly recommend.
 

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