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So I just bought a 2000 f350 7.3L diesel auto. It's lifted with 46" tires on 20s. (That's how I bought it today) I am curious without dropping lift and tire size will a chip or programmer even touch my mpg to help me gain? I'm learning about powerstrokes now that I'm out of my 1st Gen. Any advice would be greatly appreciated.
Look in to a Hydra Tuner. The Hydra holds 15 tunes, and is very easy to download updates and revisions to. As far as an mpg increase, I don't think you'll see much of a difference though. Maybe 1 mpg, if you can manage to keep your foot out of the pedal with the new found power. Just to much rolling mass. I'm gonna take a guess that you get about 12-13 mpg now.
The Hydra with Gear Head tunes is your best bang for the buck right now.
Will it help with the MPG's on that lift kit and tires, probably not...
Take a look at my signature for the MPG's I get with no load and towing a 12K lbs 5th wheel. I have stock sized tires and wheels though. Also, the truck is in top running shape with all sensors and mechanical parts working as intended. (Except for the clutch, which is being replaced right now).
If you go back to stock sized wheels and tires you'll need to change back to stock gearing, 3.73/4.10 or your economy will be worse than it is now. Get everything 100% then think about that chip.
Slowing down a bit.... 3200 RPM? That's near redline on the 7.3L. I can't see this rig running redline on the highway, unless you've either lost a gear (or two) or the torque converter isn't locking.
A "normal" tire is 32" in diameter, and you have 46". Using a little algebra here, pi times the diameter of a stock tire works out to about 100" of rolling distance per revolution. Then... pi times your 46" tires equals 144" of rolling distance for each spin of the wheel. A 44% increase in distance traveled vs. what's reported on the odometer means you are getting 14.5 - 17 MPG. I say before you chip, I'd drive down the road while seeking out mile markers. Verify that your odo (and speedo) is off by about the amount I mention here.
Oh... and no amount of chipping has ever really helped fuel economy, that is one thing the factory got right. Then... it's just a matter of the closer the truck is to factory, the better the fuel economy - air dams and suspension drops notwithstanding.
Thank you for the help!! I will do this as soon as i can. If I have to drop it I would drop it. Thank you everyone for so much time and words. I appreciate all the help I can get.
