All:
Will summer time heat mid 90's-100's cause fuel milage to godown. Drove from Jacksonville FL to Oklahoma city for work. I averaged 16.5 to 17.5 comming out here now my milage has gone to 15 to 15.5. Will the high Heat cause this?
Thanks

 

I wondered that myself? The other day it was friggin 105 and I was only pullin 14.3 mpg, @73 mph yeah I had the AC on but that is the worst I have got yet.

 

Since heat is a good killer of performance, it would lead me to believe that it also effects fuel milage.

the warmer the air, the less dense and the less temperature rise you get from combusting the fuel.

 

cold fuel atomizes better than hot and they will always run better on cooler air thus cold air induction if you lose performance you will lose fuel mileage ,welcome to oklahoma

 

Well, let's see Running the AC and running the truck @73mph. Compare that to NO AC and running @73mph Not me, it only make since that the fuel mileage will go down some, OH yeah add in that you got different fuel form another area of the country and there you go. I have seen a loss of 2-4 mpg with different brands of fuel, now go figure

Come on guys, it's HOT a s hadees out there so you can't cool off that condensed air the Turbo is putting into the engine, besides when you run the AC didn't you notice that the fan was coming on and dragging down the hp some

 

Thanks Guys
I always new OK sucked. Come to think about it my last two tank fulls came from OK truck stops.

 

so does anyone know why we are now paying more for diesel fuel than for a gallon of unleaded? for years diesel was cheaper than unleaded, not any more.

what gives?

david out of socal
sitting in flint, michigan

 

I had and interesting vacation and a test of fuel mileage. My wife and I drove from Mesa Az. to Kettleman city Ca., a trip of 584.6 miles and I used 26.7 gal. of diesel at max cruise control most of the time. When I do the math I get 21.895 and most of the time the mileage is 19 -20. I have a early 04 auto QC 4x4 sb 3.73 and a campershell w/airaid that all. why are my numbers so much better than many other truck owners? One thing I did different was at breakin I made many long runs at cc max to Phoenix- Sacramento. I'm at 33500 miles now.

Marc

 

My truck get better mileage the warmer it is outside. I drove back from Florida in March. It was 90* when I left and 30* when I got home. The truck got much better mileage down South in the warmer air.