What is the sweet spot as far as RPMs and mileage question
I just bought a '99 F250 4x4 x-cab and I discovered that it has 4:30 limited slip gears. I have seen before that these engines like to wind up and seem to make more of their torque and HP at higher rpms. Has anyone ever used a ScanGauge or other mileage computer with a V10 to find the best RPM as far as economy.
I use a ScanGauge constantly on mine, but not to monitor mileage. I hear on this site all the time that V10s like to "wind up", but honestly, that's BS to me. Mine consistently runs from 0-2.3k. I haven't seen 3k in over a month. It really has to do more with your gearing. For example, our 550 with the 7.3L and 4.88s has to be wound up to go basically anywhere, loaded or unloaded. It basically caps at 60-65 mph on the highway, because you run out of gearing.
__________________ 2002 F-250 - V10, Crew Cab, Short Bed, Lariat 4x4 aka My Lovely Big Girl.
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Well for MPG from what I have seen on my 09 is once I am in OD (say 1,500) it goes down hill from there. I definetly get higher mpg cruising around in 5th at 45mph than 65mph, and better at 65 than 75... So for economy I'd say the slower the better as long as you can hold OD without bogging it. Now for towing, having the rpms a bit higher might help hold OD more...
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09 F-350 V10 4x4 6spd CC/8' ordered 5/26/09 delivered 7/6/09
99 F-150 4x4 Reg/Short bed
78 Big Bronco 4x4 (a work in progress)
84 Tbird (351W project still in dry dock)
For simple empty highway cruising, I get my best mileage around 65-68 MPH. I have a 2 valve V10, 3.73's and stock size tires.
I can't remember what RPM I'm running, but I believe it is right around 1800-1900 RPM or so. I may be wrong...? But in the grand scheme of things, I consistently average the same numbers over the 64,000 miles i've put on this truck. I really only get the 14+ numbers when I'm really trying to save the fuel, and when traffic conditions allow it. Other wise it's the same old numbers.
As far as gearing goes, it really depends on how your using the truck. I've got 3.73's, and for my uses I really need deeper gears. It seems I'm winding up the engine longer and more often on a day to day basis driving and towing the way I am.
There are days when I love the 3.73's and there are days when I wish I had some 5.38's. I guess it's the "grass is greener on the other side" scenario.
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1999 F250 Extended Cab/Short bed, V10, Auto, 4x4
235/85/16 BFG MT
12k Warn winch/Transformer bumper
164,000 miles and counting
My 2 cents. What i have noticed is the 99 year models V10's from the factory have a high RPM shift strategy in factory form paticularly from 2-3 shifts. PCM codes AEO1 and AEO2 ....
For simple empty highway cruising, I get my best mileage around 65-68 MPH. I have a 2 valve V10, 3.73's and stock size tires.
I can't remember what RPM I'm running, but I believe it is right around 1800-1900 RPM or so. I may be wrong...? But in the grand scheme of things, I consistently average the same numbers over the 64,000 miles i've put on this truck. I really only get the 14+ numbers when I'm really trying to save the fuel, and when traffic conditions allow it. Other wise it's the same old numbers.
+1 on this, If you keep the RPM's under 2K and take your time getting up to speed you will see the best mileage. For my 01 it's 65MPH and below that I get the best mileage. For empty highway cruising I have never had to push it above 3K RPM wise either. I've got the 3.73s in the rear and am running 285/75/16's for tires.
My 2 cents. What i have noticed is the 99 year models V10's from the factory have a high RPM shift strategy in factory form paticularly from 2-3 shifts. PCM codes AEO1 and AEO2 ....
Hmm. I never knew this. Although it makes sense from what I've experienced.
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1999 F250 Extended Cab/Short bed, V10, Auto, 4x4
235/85/16 BFG MT
12k Warn winch/Transformer bumper
164,000 miles and counting
yea its something I noticed with our 99 model.. It seems as Ford uses same shift strategies for trucks that year with 3.73 and or 4.30 gear set.... Not a good idea. 2000+ year models use a lower shift pattern which we use a modified version of in all of our tunes as its much more favorable for economy and acceleration when not towing.
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