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Old 07-12-2021, 07:31 AM   #1
chrismoore701
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Wrong mileage

I just got back from the Southeastern Truck Nationals about an 800-900 mile round trip, depending on who you talk to. My truck showed 817, google showed 860 plus running around and my buddy shows 925, Thoughts on this?
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Old 07-12-2021, 07:38 AM   #2
ky-donzi
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Re: Wrong mileage

Wrong tire size. It could make your Speedo off very little, but compounded over a long trip it would show on your odometer
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Old 07-13-2021, 07:40 AM   #3
chrismoore701
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Re: Wrong mileage

Quote:
Originally Posted by ky-donzi View Post
Wrong tire size. It could make your Speedo off very little, but compounded over a long trip it would show on your odometer
I talked to the guy I was running with and we were running the same speed, so tire size does not seem to be the issue.
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Old 07-15-2021, 08:24 PM   #4
Corts60
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Re: Wrong mileage

Check your speedo against a speed app on your phone. My 88 suburban speedo shows 3 mph slower than actuality because I run 31" tires instead of the factory size.
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Old 07-15-2021, 08:51 PM   #5
TrailerTrash
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Re: Wrong mileage

Quote:
Originally Posted by Corts60 View Post
Check your speedo against a speed app on your phone. My 88 suburban speedo shows 3 mph slower than actuality because I run 31" tires instead of the factory size.
Bingo.

Going the same speed as another vehicle doesnt mean the milage will match.
Especially if one or both of your speedometers arent accurate. A few MPH on both your trucks one way or the other can add up to... well... the difference in your milage and his milage for the same trip
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Old 07-15-2021, 08:54 PM   #6
mongocanfly
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Re: Wrong mileage

GPS is what I was gonna also say..I have a handheld and checked my C30..it was off..used it to recalibrate my z71 when I went to 285s..
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