So I drive TO Dallas from Houston and get 18.4mpg, then turn around a week later and drive BACK to Houston and get 14.1mpg.

Nothing has changed with the truck, no A/C both times, averaged 71mph there and 70mph back, carried the same payload both ways. I am completely baffled! I average better than 14mpg in the city!

Anyone with any thoughts, please share. Thanks

Stephen

 

might have got a bad tank of gas

 

Come to think of it, I did fill up at a small town Exxon station on the way there... I thought Exxons were Exxons... maybe not.

 

I would bet on wind resistance, and fuel quality is a possibility.

 

Alot of people do not think of that but it plays a hugh roll on mileage ifthe wind is blowing

 

What was your payload? It could accentuate the wind resistance if it stands higher than the truck.

 

No real payload, just me and some luggage. I just meant that I didn't have 0 passengers on the way there and 3 on the way back.

I'm making the drive to Dallas again on Friday, I will post up what turns out. I'm going to top it off at a reputable Shell station so I can rule out if it was a bad tank.

 

Wind resistance, fuel quality, weight difference, altitude difference. A lot of small goofy things play huge factors
Possibly goin just a touch uphill more on the way back? Been too long since I've been to TX, forget what the terrain is like

 

You'd be surprised how variable your foot is. Did you use cruise control both ways? That's really the only way to get accurate readings.

 

As mentioned, there's alot of factors involved...almost sounds like it's down hill going there and up hill on the way back...