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V6 to GT: Whoa, why didn't my mileage drop?

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Old 06-19-2014, 12:47 PM
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GTC
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Default V6 to GT: Whoa, why didn't my mileage drop?

I traded a 2013 V6 Premium Auto with Pony Package (18" Tires) for a '14 GT Auto (19" Tires).

The GT gets about 3mpg less on the highway (25 compared with 28/29) than the V6.

But, I traded the V6 with 26,734 miles, and the average mpg for that period is 22.2mpg.* The GT, which if anything I'm driving a little faster, particularly from a stop, has gotten 23.2mpg with the odometer at 812 (it was delivered with over 300), and I was fully expecting 19mpg! So this is good yet mysterious.

*The computer mileage on the V6 tended to be about .7 lower than actual. So, maybe closer to 22.9 actual mpg. I don't know if the GT's computer leans wrong in either direction or is spot on.
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Last edited by GTC; 06-19-2014 at 12:51 PM.
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Old 06-19-2014, 01:00 PM
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jz78817
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what axle?
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Old 06-19-2014, 01:26 PM
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Originally Posted by jz78817
what axle?
Both being automatics, the standard GT has 3.15:1, and I believe the V6 had the same since the only package it had was the Pony Package which doesn't change the rear end.
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Old 06-19-2014, 01:27 PM
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Slowbra302
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I get roughly 26-29 mpg on the highway with 3.73 gears. If I draft I break 30

If I drive to fast (above 65) it's looking closer to 24 mpg
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Old 06-19-2014, 01:55 PM
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dcarlinf1
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Originally Posted by Slowbra302
If I drive to fast (above 65) it's looking closer to 24 mpg
65?!?! If you go 65 around here you will get run over by pickups and hondas. I do 80 on the local interstates. I also have 3.73 gears and get around 18-19mpg if I drive "normal". If I take it easy I can get 22-23, still doing 75 or so.
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Old 06-19-2014, 09:03 PM
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Falcon Fixer
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My non stock 2011 GT gets 27-29 at 60 depending on hills and outside temp.
I average 24-25.

ETA:7-2-14 pulled into the driveway today with a 27.1 avg.

My GT 500 14-15

Last edited by Falcon Fixer; 07-01-2014 at 06:56 PM.
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Old 06-20-2014, 10:40 AM
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dslpow3r
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I dont ever look at the computer generated gas mileage, I use it more as a reference cause not too sure how accurate it is anyway, but if I worried about gas mileage I would have bought a Prius.
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Old 06-20-2014, 10:45 AM
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Rudolph Hucker
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v6 and v8 are so close on mpg it dont matter...
i get 1 litre per 10 kilometers in my 4.6..about 25mpg..my v6 did about 26-27 mpg

Last edited by Rudolph Hucker; 06-20-2014 at 10:49 AM.
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Old 06-20-2014, 11:13 AM
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Slowbra302
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Originally Posted by dcarlinf1
65?!?! If you go 65 around here you will get run over by pickups and hondas. I do 80 on the local interstates. I also have 3.73 gears and get around 18-19mpg if I drive "normal". If I take it easy I can get 22-23, still doing 75 or so.
I know lol. In in SoCal and everyone drives wicked fast. I have learned to drive in the number 3 or 4 lane slow and generally have more run in with sweet cars. Just my thoughts lol, and at 80mph I avg 24mpg
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Old 06-20-2014, 11:14 AM
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PNYXPRESS
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It has to do with power to weight. The V6 is moving roughly the same weight as the V8 with less power, therefore it has to work harder. This is why they get roughly the same fuel mileage, even though the V6 engine is technically more efficient than the V8.
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