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Discussion Starter #1
Will the digital mpg readout work the same after getting bigger tires? I had the speedo changed by the dealer. Just wondering why my gas milage is in the sh!tter. I got 13 mpg pulling my boat 30 miles on the freeway.
 

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If your speedo was recalibrated, it should be right. I would note that the factory setting on nearly all production vehicles reads a little high, so it will still be telling you you are going faster than you are, and getting better fuel efficiency. Usually off by about 2 mph @55. 3 to 4%. But that's how they come from the factory. Close enough to not matter, but enough to save a lawsuit.

The dealer can reset it for you? I wonder if they could do my 2nd gen? I gotta ask em!
 

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It will be correct since you had the speedo recalibrated, however I use the term correct very loosely....the overhead is never tuely correct. Just hand calculate :thumbsup
 

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Yes the dealer is able to recalibrate your speedo for you, very easy to do
 

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Discussion Starter #5
cool thanks. I just am wondering why my mpg sucks. i'll figure out my milage on this tank and cross check it the the digital.
 

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Eh, I wonder if the dealer flashed the latest and greatest when they reset your speedo, and the new program is boning your efficiency? Or perhaps a previous owner had a downloader, and you just lost your program. Just an idea. Correcting the speedo should have made the mpg read better.

BTW thanks cummins6speed for the speedo tip.
 

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Discussion Starter #7
I bought the truck new, so no worries on a chip. I did notice when I drove past a digital speed sign. My speedo showed 58, and the sign said I was doing 63. But I have yet to get above 15mph?
 
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