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Old 08-06-2015, 09:23 AM   #7
FED 387
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Default Re: 2003 F350 diesel

The best MPG on a 7.3 is under 2000 RPM bout 1800 anything over1800-2000 and the MPG begins to go down QUICKLY-- mine has a 3:73 a real slug to get up to 62-65MPH but once your there it goes along nicely--- if it gets real hilly make sure to take it out of overdrive too--FED 387
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