For those trying to solve my problem. I just got an 03 4x4 SWB Hemi. It has 3.92's and 39k on it. Looks very clean and was purchased from a dealer. I hardly ever get it over 2k accelerating. Im running 89 octane which is recommended in the manual. So far its all around town. My first tankful was the dealer fuel and it wasnt quite reset at 0 so it averaged about 11... now from a fresh tank to less than 1/2 tank im at just around 12mpg. I know the on board isnt always accurate but if the trend continues i will have gone about 300 miles on 25-26 gallons= 12mpg

 

thats crazy as hell unless 89 makes that much of difference alls i run is 93 in mine hell with all that sludge know what i mean

 

My truck gets no better than 10 mpg in town, though I admit to frequent use of the pedal. I plan to do plugs & wires when it gets warmer because it's got 55k miles now.

I run only 93 octane because once you're paying to fill this tank it really doesn't matter if it's a few extra dollars.

 

With all in town driving, that sounds about right. Luckily 80% of my driving is highway/interstate. Around town it sux it down pretty fast...

 

hey bwhite. on your exhaust..do you have a muffler or did you take it off? what size tips do you have? cuz i have a flowmaster 50 series dual wit 3in tips and i watched your video and yours sounds louder than mine ha. jus wonderin. im thinkin bout switchin my muffler to a 40 series