Better Gas Mileage.....Why???

[opticsguy]

Just completed a 2500 mile round trip. I found that the wind makes a lot more difference than anything. With a 20 MPH tailwind I regularly got 32 MPG (per the computer) for hundreds of miles. When the wind shifted to a crosswind in IL, the MPG went down to 29-30. Fighting a 25 mph headwind in OK and TX I got 28. My best MPG was in normal mode, but then again it was with a tailwind.

Get behind a truck on the freeway and watch the mile-o-meter go up 3-4 MPG.

 

[txvmax]

txvmax, that's interesting info. Do you happen to know if you've had the V8 ECM recall?

Thanks for the response. I've not heard about an ECM recall. Maybe they did it when they put the new tires on? I've got 11k on it so far and it's a year old this month. Also, I didn't think about this but I did swap to K/N air filters straight away.

 

[G-178275]

I have a 15 Ultimate 5.0. I have found that I can regularly get 1.5-2mpg (2 on Hwy) better gas mileage if I drive in Sport mode versus Eco mode. Is this due to shifting points or holding gears longer. I've been experimenting over the past 4 months and it's true. Any ideas?

The reason being is that your engine has reached optimal performance. I have had to BMW's a 745 Li and now a 750Li and they both had better mileage at high speeds. In the case of these two vehicles, the best speed for best fuel consumption was between 120 to 125kmh. Once I exceeded that speed, the consumption would begin to drop.

 

[lobsenza]

After reading all the responses so far (thank you) I did a more in depth test. Same route same time of day (so traffic would be equal). I drove until an indicated 3 miles left in tank. Put 5 gallons in and drove route in Eco mode ( 91 miles - 18.2 mpg). Then back to 3 miles indicated and 5 gallons but in Sport mode (99 miles - 19.8 mpg avg). This was combined city/highway. I kept car under 3,500 rpm as to try and keep things equal. So...works on my car, not scientific but any gain is worth it. I tried to keep acceleration the same and speed was 75 on highway. 8th gear is not an issue in sport mode for me. I also prefer the stiffer steering in sport as well. So get in.. Activate auto-hold then go to sport. In my instansance over a full tank it does pay off.

I think you would be better off running the test and refilling the tank to full after each test. The MPG meter distance to empty is based on your driving, so the amount of fuel left with 3 miles to empty will vary. In addition, draining the tank that low is not good for the fuel pump.