Comprehensive MPG thread.

Mine 6.7 is at 8k miles, and I don't see any increase in mileage either. I am reliably around 15-16 in Dallas stop and go traffic, and 21 on under 85mph unloaded highway. I have touched close to 23 on some slower, flat, no wind highway driving, but that appears to be "best case scenario" mileage unless I can find a 600 mile downhill stretch with a 40mph tailwind. :LOL:

Ed
 
I finally took a proper mostly-highway reading of MPG with the 37x12.50r20 tires. Each wheel/tire weighs about 120 lbs each... That is impressive.

23 gallons consumed. Regen took place during the run. Engine had to warm up only once. Same station, same pump. I took into account the different tire diameter. 17.7 mpg overall.
 
That region party only last for 30 or less minutes.....will get crappy milage at that time but will jump right back up afterwards. Still have the 19 mpg average after 1200 miles and 15 while towing the boat. 3500 miles left on the DEF tank.
 
2021 7.3L, XLT, just hit 1000 miles

1st tank:
Lie-o-meter: 12.5-----Actual: 12.75

2nd tank:
Lie-o-meter: 13.9-----Actual: 12.39

3rd tank:
Lie-o-meter: 14.5-----Actual: 13.31 I had to drive it really easy to get this. Didn't get over 60 MPH most of tank.
 
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2021 7.3L, XLT, just hit 1000 miles

1st tank:
Lie-o-meter: 12.5-----Actual: 12.75

2nd tank:
Lie-o-meter: 13.9-----Actual: 12.39

3rd tank:
Lie-o-meter: 14.5-----Actual: 13.31 I had to drive it really easy to get this. Didn't get over 60 MPH most of tank.
Fairly consistent
 
2021 7.3L, XLT, just hit 1000 miles

1st tank:
Lie-o-meter: 12.5-----Actual: 12.75

2nd tank:
Lie-o-meter: 13.9-----Actual: 12.39

3rd tank:
Lie-o-meter: 14.5-----Actual: 13.31 I had to drive it really easy to get this. Didn't get over 60 MPH most of tank.
City highway what are the driving conditions? What caused the disparity with the first tank? TFL records their mpg fairly accurately and they seemingly are all within 1 mpg of the readouts.
And disappointing
What did you expect? Considering the 6.7 of 2019 was hitting 13/14 consistently.
 
And disappointing
A little. But it's relative. I fully expected it when I bought this truck, and I only expect it to improve as the engine breaks in. It would be nice to get about 15 MPG, but I don't think that will happen.
 
City highway what are the driving conditions? What caused the disparity with the first tank? TFL records their mpg fairly accurately and they seemingly are all within 1 mpg of the readouts.
My daily commute is 11.5 miles each way--a mix of country 2 lanes (45-55 limit), some stop and go city (35 limit) with several red lights, and some split 4 lane highway (55 limit). About equal percentage of each. Weekends are mostly 2 lane country roads, with some open highway. I start out slowly and drive like a grandpa most of the time. But I have got on it a few times. The last tank was definitely more highway miles, but it was rolling with a good bit of hills. I stayed around 60 on most of it.
I have no idea why it was like that on the first tank. I don't have an explanation for any of the disparity. I just reset the computer each time and go. And I usually let the pump kick off and don't top it off, although I guess the pump could kick off in different place.
 
So far, so good. If I can consistently get over 13 MPG, empty, mixed driving, then I'll be pleased. That's only a 2-3 MPG penalty from my 2018 Cummins
Here’s my Actual results w/ the 7.3L for those that are curious.
Keep in mind all I do is city driving, I’ve only been on 2 road trips in 11,000 miles.

10.8 MPG and I’m not surprised nor do I care. Hahaha!!
 
7.3 F250 gasser @1000 miles combined mileage of 11.2 mpg. I drive 12 miles to work and 12 miles back,4 miles being surface streets and 8 miles on the freeway. The hardest thing to get used to coming from the 6.7liter diesel is the tank size combined with the mileage always makes you feel like you need to stop and get fuel?
 
Just completed a trip from Orange County , CA to Phoenix and back. Unloaded. I travaled at 80 to 85 the whole way. I averaged 18.2 by the end. I can say I was expecting better. I only have 1k mileages on the truck after the trip so I hope it improves over the next couple thousand miles.
 
7.3 F250 gasser @1000 miles combined mileage of 11.2 mpg. I drive 12 miles to work and 12 miles back,4 miles being surface streets and 8 miles on the freeway. The hardest thing to get used to coming from the 6.7liter diesel is the tank size combined with the mileage always makes you feel like you need to stop and get fuel?
Yes, completely agree about the inadequate tank size! I think 45 gallons would be about right, considering the mileage these are capable of (or not capable of), especially if you were towing.
 
Yes, completely agree about the inadequate tank size! I think 45 gallons would be about right, considering the mileage these are capable of (or not capable of), especially if you were towing.

I don't know if it's been highlighted in this thread, but there's a petition to show Transfer Flow the interest in a bigger CCSB super duty gas tank.

 
My daily commute is 11.5 miles each way--a mix of country 2 lanes (45-55 limit), some stop and go city (35 limit) with several red lights, and some split 4 lane highway (55 limit). About equal percentage of each. Weekends are mostly 2 lane country roads, with some open highway. I start out slowly and drive like a grandpa most of the time. But I have got on it a few times. The last tank was definitely more highway miles, but it was rolling with a good bit of hills. I stayed around 60 on most of it.
I have no idea why it was like that on the first tank. I don't have an explanation for any of the disparity. I just reset the computer each time and go. And I usually let the pump kick off and don't top it off, although I guess the pump could kick off in different place.
Thanks.

I’m at 10k miles. I’m getting 12-13 city and 14 or about with back country road(switchback climbs and descents) and highway. I drove up to Reno 0-7k-5k altitude in the Sierra traveling 70/75 and I was at 13mpg.
I see about 1 mpg less when not in eco in the city. Less of a difference with eco on the highway.
Here’s my Actual results w/ the 7.3L for those that are curious.
Keep in mind all I do is city driving, I’ve only been on 2 road trips in 11,000 miles.

10.8 MPG and I’m not surprised nor do I care. Hahaha!!
Hammer down
7.3 F250 gasser @1000 miles combined mileage of 11.2 mpg. I drive 12 miles to work and 12 miles back,4 miles being surface streets and 8 miles on the freeway. The hardest thing to get used to coming from the 6.7liter diesel is the tank size combined with the mileage always makes you feel like you need to stop and get fuel?
Stops kill mileage. I’ve noticed 16mpg fresh gas if I hit lights and 12mpg if I don’t same drive home.
Yes, completely agree about the inadequate tank size! I think 45 gallons would be about right, considering the mileage these are capable of (or not capable of), especially if you were towing.
Why? I’m getting 420 miles on my tank(30-32 gallons) my last vehicles could only go about 300-330 miles before fill up.
At 400 miles I can drive from Napa to Hollywood no problem. 6-7 hour drive most need bathroom or food at that point.
My only complaint is the $2.50 tax per gallon ca levees.
 
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