Over inflating tires better mpg on long road trips?

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Supercup

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Tire pressures will effect mileage and ride quality so it is a trade off. Door jamb pressures on 2014 SCrew is 44 psi front and rear. Many folks run in the 35 - 38 psi range.

I have 17,987 miles in my truck in 6.5 months, I commute about 650 miles per week. What I found to date is I have used 1,500.5 gallons, per the truck computer and averaged 11.99 mpg.

I have seen a high of 14.2 (my wife was drove 1 tank of fuel on a trip about 70 mph) and a low of 9.1 (a day of offroading in Barstow). I get between 11.4 and 12.2 on my weekly commute - depending on traffic and how hard I drive. I am able to drive around traffic times most of the time and drive early and at 80 - 90 mph. If I drop to 70 mph I see a considerable increase in mileage.

If you go with 44 psi front and rear, are light on the throttle and drive 70 or less you will likely get pretty good mileage. I even decided to try it one day, but only got halfway to the office and I was going 90 again. Thank goodness for the lowered gas prices.

Trial and error will get you the best results for your needs - good luck!
 

SuperRaptor

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Some clown posted on FB that he was getting 16-18 mpg. That too me sounds like you're either playing a video game or you've never owned a raptor. Who can drive these lightly? When the light turns green, I always check my 0-60. :-D

I would be skeptical of that as an average with stop/go/etc but I did average over 18 from Seattle to Portland. Tires were at ~46 PSI
 

Mad Max

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When I was on Method NV's and 35's...

Back roads (40-55), I could get 20 mpg with my 5-star tune and using throttle management - I'd lift off the pedal slightly and slowly bleed off a little speed on any uphills. I'd keep it in M6 and wouldn't get under 35 (or it down-shifts to 5th). During "normal" driving and Interstate (65+), I'd drop to mid-teens. Or drive it like you mean it, lots of WOT and 80+, then I'm under teens and at times hitting single digits. The Methods NVs are a bit lighter than the factory wheels and any rotational weight you can remove makes a significant difference. But mostly, it just comes down to your driving style or habits.

Now that I'm running a 93 Performance Tune (and on 37's)... I eventually stopped caring about the mpg lol

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155mm

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there's a drastic difference between over inflation of the door sticker pressure, and the sidewall max pressure.

The door sticker is what, 35 psi? The tire sidewall says 50 or 55 psi. The door jamb sticker is given for a mix of comfortable ride, handling, capacity, etc. The sidewall number is for max tire payload the max pressure you should safely run.

I always run mine a few psi above the door jamb sticker because I don't check it as often as I should, so when it slowly drops over time, by the time I check it and top it off again it's still at or above the door jamb sticker. I also measure my tire tread center and outer at every 5k tire rotation I do and they're wearing evenly. IIRC the door jamb says 35 and I run ~38 and tires are wearing great.

Now if I'm towing (~7500-8000 lbs), I'll bump the rears up to 50. It definitely helps stability when towing as well. If I've got a long road trip (3-4 hours or more) I'll bump all 4 up to 50. Rides slightly rougher, but hey every bit helps on fuel economy. It's over-inflating in the sense of the door jamb rating, but not over inflating in the sense of the tire's safe limit. For an hour drive or so, I don't bother, I leave them at 38ish.

I'm pretty sure the recommended pressure is 44psi, not 35.
 

cbcgeneral

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I would kill for 15 MPG. Since I drive like a douch bag i get 10.3. But then again I wasn't thinking about gas when I bought either truck. I must need to take a driving class because I only get about 12MPG in the Shelby and the window sticker said 25MPG. :boxed:
 
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