recalibrating speedometer

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Dec 11, 2008 | 04:59 PM

rootercycles

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recalibrating speedometer

I put 295/70R/17 on my truck. Do I need to have the speedometer recalibrated? I don't have an aftermarket ECM so does the dealer have to do this?

Dec 11, 2008 | 05:07 PM

BigIron70

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From: Sunny Southern California Land of Fruits and Nuts

Dealer needs to set PCM for that tire size. Check out this web site you can compare tire size to see how far off the speedo is with current tire size.
http://www.miata.net/garage/tirecalc.html

Dec 11, 2008 | 05:27 PM

rootercycles

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great calculator! Thanks!

Dec 11, 2008 | 06:08 PM

mikmaze

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From: Cedar Grove, New Jersey

if the dealer isn't sure how, kindly let him look in the abs menu, I think that is where you set revolutions per miles on that year truck..... others feel free to correct me.