Highway gas mileage sucks.

FWIW: today’s trip up I95 from Northern VA to Philly area averaged about 26mpg. Some hills, especially on DC beltway. This screen cap from a pit stop in MD to home. Went easy on the pedal, no cruise control, no ECT, between 60-75 most of the way. Tires inflated to 39psi but up to 41 at hwy speed. I have a ‘17, DBL CAB LB, 4wd. Just me and a passenger, no load.

 

Anything over 70mph and i begin to suffer... I noticed here, wind plays a huge factor, i'll get 23mpg one day going 70mph, next day i'll be down to 19.5mpg.

 

Curious what the expectations are? I'm happy with my 18 mpg average with mixed city and interstate driving. I drive hard too and 80 mph on the interstate.

I have reasonable expectations as our other vechicle is 2015 highlander awd with the same 3.5. I average low 20's for mpg when I drive it.

 

I’m getting 22 with 285 Toyo at2

 

Downhill with a tailwind? Calling total BS there

 

More like around 19.5

 

I wonder if adding the pro skid might gain better mpg, any confirmations?

 

With stock tires or anything close to them, getting 22mpg is extremely easy.

I have gotten up to 24-25mpg if I keep it around 50-60mpg, and drive like a grandma.

Although it is common to see people fill up their vehicle, drive a few miles downhill and claim they regularly get 28+mpg lol, best way is too show a nearly empty tank or trip mpg so I understand skepticism here lol.

 

I am root

 

I did that once in my Saab going down hill with my foot off the gas and got 99+mpg!

In addition, in the winter air is colder and more dense, increasing wind resistance, combined with the oxygenated gas we get up north and you end up with horrible mileage.
Wind resistance increases with the square of the speed .

For some real physics on this and an interesting chart on the 55 to 65 mph that seems to get the best mileage check this out. Skip to the end to see the horsepower needed going 55 vs 60mph.

http://www.phors.locost7.info/phors06.htm


This is a great site for speed mpg and cost comparisons.
http://www.mpgforspeed.com/

 

Very interesting read!

 

Saw 23-24 mpg during initial 1k mile break-in. Drove it like a sewing machine.

 

2000 rpms at 60? My auto is 2000 rpms at 79.

 

Great read, thanks. In my testing I've found that 45-50 is the best speed for MPG in these trucks. I try to keep it in 6th gear (auto) at around 1100 RPM and I have gotten up to 27 MPG but average 25MPG in my regular commute of 25 miles(50 round trip). When I go onto the highway at 65-70 mileage drops off a cliff down to 22 to 20 depending on wind. This is in Maine too, if it is true that winter gas and cold air have a significant impact on mileage, then I am interested to see what things will be like in the summer.

 

Will the sport mode of the transmission do anything to help allow the RPMs to stay lower in hilly driving and reduce some of the high RPM downshifts? Haven't had a chance to experiment yet. My previous Ford with monster tires that each weighed 78 lbs was getting 9-11 MPH so my 22-23 at 65 is wonderful. My wife complains I am now driving like an old man but I am trying to "milk" high MPG tank results by not making my engine downshift on hilly highways..... it only makes me arrive a minute or two later I think.

 

No, the gear you set in sport mode is telling the computer the highest gear you want the truck to shift into. Set it to 4 and the computer will do its best to never shift to 5. So its actually the opposite of what you want and it would only ever be able to keep your RPMs higher by locking out overdrive gears.

 

maybe it’s just me but the cruise control on my truck is pitiful... We don’t have a lot of really steep hills where I live and the cruise will cause the rpm to go up to almost 4000 going up a small hill after downshifting down a hill. Very touchy so I don’t use it much and get 19-21 mpg @ 65 -75 mph depending on the highway with ECT off. Window sticker said 23 Highway I think LOL

 

I kinda know what you are talking about. Sometimes it will hold a low gear too long as well, and run 4k RPMs for far too long. When I get into hilly areas I usually take manual control.