My First Tank Of Gas MPG

[Cgs1967]

In the winter time your mileage will drop. One reason is cold air is denser. The molecules are closer together. This tricks the ECM to think the motor needs more fuel to match the air going in and will dump more fuel in than needed. Motors rum rich in the winter because of this.

 

[theblet]

And make more power

 

[1D32319]

I'm not going to trust the first tank. Bought the truck Friday, but I didn't reset the trip odometer until late Saturday. The computer(which I don't trust) has been sitting in the high 18s for most of my drives. Even hit 19.1 today.

I'll probably fill up Tuesday or Wednesday and will run a few tanks and hand calculate it. After that, I won't worry about it. Nobody buys a full size 4WD truck(even just a half ton) with an 8 cylinder and 3.92 gear ratio for good gas mileage.

 

[yankeefan31569]

summer blend gas you w see a differnce between winter and summer run 89 less knocking and engine pings

 

[Kenny4]

The above is right on. Last time I looked at the hour monitor, it showed 3 hours at idle vs 31 hours driving. So that is 10% right there.

 

[21Bighornnightedition]

The above is right on. Last time I looked at the hour monitor, it showed 3 hours at idle vs 31 hours driving. So that is 10% right there.

2021 1500 Big Horn Hemi
eTorque 3:21 gear.
Potential good news to report.
Got my first fill up today at 398 miles. There were 3 miles on it and full tank when I picked it up at the dealership. Took 20.0007 gallons 87 octane, so 19.75 mpg. Computer said 18.4 average. Of the first miles 270 were NJ and PA turnpike fairly constant 70 mph. Balance of miles mostly 10-15 mile trips averaging 40-45 mph. No city stop and go. Left the auto stop start on constant and did my best to keep the "eco" light glowing without being a PIA or in the way.
Very happy with this first result and hoping it continues.

 

[Patamaran]

2021 bighorn, 5.7 non-etorque, 3.21 gears.
First tank got 406 miles, used 22.9 gallons. So 17.72 Mpg (13.27 L/100km) About 75% hwy, 25% city. About a dozen short 10 mile trips at about 45mph though. That seemed to have eaten into the fuel efficiency, as it was doing much better before that.

For a first tank, that isn't bad. Hopefully after the first service I gain a tiny bit and that would be plenty for me.