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Discussion Starter #1
I guess I'll start this thread dedicated to the Mileage Max. Others that have one post up your results. My first tank was very disappointing. I used the overhead odometer to calculate.

Before mods, all stock I got 16.3 (hand calc'd) on my last tank. City/Highway/Idle

After mods and new 285/70 Michelins I got 14.3 (hand calc'd)!!! Terrible. City/Highway/Idle

Could the new tires have thrown off the overhead odometer that much??? The overhead "lyometer" was higher than normal. 14.3 is just not gonna cut it!!! Are there any other factors that could have contributed to the piss poor mileage???
 

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Overhead is always off. Best to do odometer/gal. to fill.
 

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my overhead ODO matches my dash ODO....I am pretty sure the info is the same. The AVG fuel economy is another matter....
 

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Discussion Starter #5
my overhead ODO matches my dash ODO....I am pretty sure the info is the same. The AVG fuel economy is another matter....
I knew the Avg Fuel Econ was :BS:. I figured the 2 odometers matched. That means my mileage sucks!!! :mad:
 

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how many miles are on the truck?
 

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multiply your miles for that specific tank of gas by 1.035....then divide by the amount of gas you used to fill the tank....
 

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have you changed the fuel filter recently?

I get about 15mpg around town with some highway. heck....straight highway, the most I can get is 17....
 

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Discussion Starter #14
I changed the fuel filter about 500 miles ago. I know the motor is not even close to being broken in but I figured the Mileage Max would IMPROVE my mileage.
 

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I changed the fuel filter about 500 miles ago. I know the motor is not even close to being broken in but I figured the Mileage Max would IMPROVE my mileage.
Yeah but one time tank comparisons are kinda like blood pressure readings. For the short term, can pick out problems but for the best info long term comparisons are needed. That is one of the biggest bummers with diesels is the long engine break in period.
 

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Discussion Starter #16
Yeah I guess your right rufushusky. I was just hoping for immediate results. Is there any other chip/module that could give me immediate results, such as a Smarty? I was thinking of getting one.
 

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did you add the tires and the leveling kit at the same time?

Believe it or not, just raising the nose of your truck will hurtmilage. We turned the torsion bars up on a buddy's duramax and he lost 2mpg. Dropped the back to stock and he gained the 2mpg back.

Lift and bigger tires are your enemy when it comes to milage.
 

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Discussion Starter #19
Well, I just filled up again. This tank was better. 16.38 Hand calc'd. My last tank was 14.8 so I'll take 16.38. I'm keeping a log now so I can get some very accurate data.
 

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Discussion Starter #20
Another tank down and I got 14.59. I must say that about 200 miles of that was towing about 5K. It did well towing, stayed in overdrive most of the time.
 
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