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Gas mileage on 2024 HD gas engine

I always keep track of MPG in my vehicles. I have never noticed a measurable improvement after "engine break in".

I get about 12 in short trips in town and 15-16 on the highway. 10-11 recently towing 5K lbs 100% highway. I knew it would be bad but maybe not this bad.

These massive displacement engines have large degrease in efficiency in short trips. Each start, each minute idling at a stop light have a larger affect on MPG.
 

Viking Truck said:
I always keep track of MPG in my vehicles. I have never noticed a measurable improvement after "engine break in".

I get about 12 in short trips in town and 15-16 on the highway. 10-11 recently towing 5K lbs 100% highway. I knew it would be bad but maybe not this bad.

These massive displacement engines have large degrease in efficiency in short trips. Each start, each minute idling at a stop light have a larger affect on MPG.
Click to expand...

I'm around same with you but at 10-11 MPG in short trips, hehe.

I was stuck in a casino parking garage for about 20mins, after a concert, all that idling and slow moving to exit tanked my MPG down to what i think was 8 MPG, was crazy, hehe.
 

xOperator said:
I'm around same with you but at 10-11 MPG in short trips, hehe.

I was stuck in a casino parking garage for about 20mins, after a concert, all that idling and slow moving to exit tanked my MPG down to what i think was 8 MPG, was crazy, hehe.
Click to expand...
Try Upside and Shell Rewards. I save like .25 a gallon using both, on top of the return on the card. I also write fuel off. I have to maximize the savings when having thirsty vehicles. I used to have a unicorn 2007 classic chevy 8.1/Alison. Lost it in my last business sale, but that baby was even more thirsty!
 

In the dash display on the OP's truck, he's showing the mpg over a 450-mile range. If you change the range (push the menu button) you can change it to a 25- or 50-mile range. The lower the mileage range, the higher the overall mpg will show as you often get good mileage in short bursts. If you really want to see your accurate per tank mileage, go up two windows to the TRIP 1 or TRIP 2 mileage gauge and you'll show your actual MPG per each tank.

My 6.2L only has about 700 miles. it's getting 13.2, but that is pretty much around town mileage only. I'm retired, so no long drives. On a couple of freeway trips it jumped up pretty fast. Saw 19 mpg as the highest mpg achieved.
 

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Now that it’s winter my mileage is really bad because I pre start my truck every time I use it so it’s warm when I leave for work and come home everyday.
 

yzf1999 said:
Now that it’s winter my mileage is really bad because I pre start my truck every time I use it so it’s warm when I leave for work and come home everyday.
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Yep... that's what my wife likes to do as well. The cost of luxury and convenience.
 

I warm up until it falls to 7xx rpms, then I'm off. With heated wheel and seat, pretty comfortable from the gate. Never thought I'd use the hot wheel, but it's now one of my favorite features. These transmissions are slow as hell to engage/change gear from P, to D, or R when cold though.
 

I don't see a shifting difference.

Do the 6.6g have the electric cab heater? That's a winter life changing design! 🥶
 

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