Have you guy's all of a sudden had a jump in MPG? I have a 03 F350 RC 4x4 V10 4sp auto 3.37ls with 36,000 miles since i bought it new and it has always got 12.5 MPG on shell gas. Well my last tank hand figured at 14 MPG and this tank I am on is going to surpass that. Whats strange is I have only done routine service as called for and have done nothing recently. I drive the same route same speed, fill the tank the same nothing has changed but the jump in mileage.
I check the numbers at every fill up looking for a drop the could indicate a problem but never dreamed it would jump like this. Wondering if any of you have noticed anything like it?

 

since the new fuel laws started i have seen the same thing . 1.2.or .3 better per gal. most have to do with the way the alcohol in the gas now burns. i also know it's a little smoother. but at the same time i am now hopefully done changeing fuel filters, as since we have gotten it here i felt a loss of power 2 times. changed the filter and it was back. each filter had a jet black gummy gas drain out of it. telling me what ever crude had built up inside my tank an't there any more.

 

I might have to check that out myself. I always got 14 mpg on my 98 club wagon though. My wife drove it & got 18 & I stopped checking after that little performance.

 

Very interesting. Mine just went up from 10-ish to 11.5. It very clearly happened, but I have absolutely no idea why.......

 

winter blend is gone, summer blend is here. could that be it?

 

This last full tank is lasting longer than expected for me too.

I'll check the mileage when I fill up again. It's almost all (90%+) stop and go so we'll see.

Summer blend does sound reasonable. Although I think here on Long Island, we're all supposed to be running E10 all-year-round, I thought.

We'll see...

 

Can you guys send some of that high mpg gas out here to CA. please?

 

I've seen better mileage too but I wrote it off to the truck have 19K on it now / loosening up. We've had summer and winter blends for several years. Always gets better in the summer as temp warms up too. I'm not complaining though!!

 

Cap I have have ran many many gal of ethenol in the truck never done that before. I Wasn't clear earlier this is in town and coutry roads, I am getting close to to what I was getting on the highway. never had that much of a change with winter and summer gas. The should no longer have winter and summer gas with the new ethenol should make gas line freeze up a thing of the past.

 

i would love to know,is it the newest blends of gas as the pumps have new stickers on them same with the diesel pumps new stickers showing new blends. or the fact that mine has a fresh reflash to cure 2 problems i had? or the combo.it's smoother but has a loose of power since the reflash also. time to spend computer time and make up some new tunes for the new code into the excal2

 

My last tank was worse than the previous 7 or so. Figures

 

A friend of mine has a Chevy V8 and his wife mistakenly put premium in the tank. He told me that he notice an increase in MPG. The reason I bring this up is that Ethonal does increase the octane and of course higer octane is what you get with premium fuel.

Rob

 

I thought it was not letting it warm up in the morning, but I am getting 1-2 mpgs more too.

 

The ONLY reason that Chevy V8 would get better MPGs is because the computer was smart enough to advance the timing.

Higher octane, all things staying the same (timing/compression) will give you LESS mpgs because you can't take advantage of the higher octane.

That Chevy must advance the timing until it pings and then backs off. Same thing the V10 does, but it's meant to live on 87.

 

That really surprises me. I can understand that using higher octane would cost more per mile because of the higher price of the fuel. I don't understand how use a higher octane fuel would actually lower your MPG.