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True Mileage

Heavyd1980
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  • 3 weeks later...
Prowelder

Prowelder

Posted
Posted

If you have a SMARTY, you can recalibrate the speedometer. However, if you use anothers to load in the calibration and then take the SMARTY off, you will loose the calibration.:2cents:

Yep White01 tried to flash mine but when he pulled the tune out, so did the recalibration... So mine is off too. I average somewhere in the mid to upper 16s with the 315s, recorrected for the size. I would love to get my speedo reflashed but I worry about the cost too. Might have to check into it, it would be nice to know how fast/far I really am going. I do know that I lost about a mile on my trip to school everyday after the tires... I don't think the road got any shorter either!!:lmao2::lmao: It would be awesome to have my own Smarty but I just don't have the money for it right now and really don't have the air for the extra fuel either!!:cry: Back when I had the 285s on it, I averaged 17.8-18 driving mostly highway and better than that on long trips to Tulsa or Lawrence.:thumb1:
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Prowelder

Prowelder

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Winslow the 16 your getting is that anywhere you drive? Highway city???

Yeah that's just my average, mostly highway. Right now I haven't been getting quite that b/c of the winter blend and the use of 4wd... and the skinny pedal in the snow.....:whistle::lmao2: And that's driving about 60-65, sometimes up into 70, just depends where I'm at.:thumb1:
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runit02

runit02

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Since the smarty isn't for everyone I'd certainly give this a look see. I havent installed or used one myself fwiw http://www.superlift.com/accessories/truspeed.asp Now to contribute, I average just under 20mpg driving 40% city 60% highway.6 speed 4x4 315/75/16's. I do relatively short warm ups, good air pressure and always leave my house in plenty of time to reach my destination, driving habits dictate whether I get 14 mpg or 20.

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Prowelder

Prowelder

Posted
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Since the smarty isn't for everyone I'd certainly give this a look see. I havent installed or used one myself fwiw http://www.superlift.com/accessories/truspeed.asp Now to contribute, I average just under 20mpg driving 40% city 60% highway.6 speed 4x4 315/75/16's. I do relatively short warm ups, good air pressure and always leave my house in plenty of time to reach my destination, driving habits dictate whether I get 14 mpg or 20.

Cool deal man, I'll check into that!!:hyper:
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Blueox01

Blueox01

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Ok guys I have 315-75's on my truck and I believe that my mph is off about 13% so if i am trying to calcuate my correct mpg would i take my total mpg' per tank and multiply by 13%??? :shrug:If i am thinking right this should give me an accurate mpg. Any help is much appreciated.

Going here might help http://www.grimmjeeper.com/gears.html as far as helping to figure how far off you are,you can compare your stock drivetrain/tires vs. new tire size.:shrug:
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guesswho512

guesswho512

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guys, the thing to remember is it is a percentage. the faster you go, the more they are off (bigger or smaller) 5% of 100 = 20 but 5% of 200= 40. it is still 5 %, the same with tires, you can only estimate MPG, but speed is easy, look for a radar detector that post your speed. my 31s, i was driving 2mph fast at 25 and 5mph to fast at 60. drive slower for oversize tires to avoid tickets :2cents:

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Prowelder

Prowelder

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guys, the thing to remember is it is a percentage. the faster you go, the more they are off (bigger or smaller) 5% of 100 = 20 but 5% of 200= 40. it is still 5 %, the same with tires, you can only estimate MPG, but speed is easy, look for a radar detector that post your speed. my 31s, i was driving 2mph fast at 25 and 5mph to fast at 60. drive slower for oversize tires to avoid tickets :2cents:

Yeah mine when it goes through the speed checker shows that I'm going 64 when my speedo says 60.:thumb1:
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dracozny

dracozny

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that truspeed box is really meant for a vehicle that has tires beyond the size limit in the ABS which is somewhere in the 40" range if i remember correctly. below that I would just look into getting a http://www.hypertech.com/products-speedometer-calibrator.aspx plugs in just like a smarty but only deals with the tires, and on a plus it pulls your DTC's too. i don't own this but I have a hypertech III that does the same thing plus some tuning.

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Prowelder

Prowelder

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that truspeed box is really meant for a vehicle that has tires beyond the size limit in the ABS which is somewhere in the 40" range if i remember correctly. below that I would just look into getting a http://www.hypertech.com/products-speedometer-calibrator.aspx plugs in just like a smarty but only deals with the tires, and on a plus it pulls your DTC's too. i don't own this but I have a hypertech III that does the same thing plus some tuning.

I might look into that, it would be nice to have the right speed!!:lmao:
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