ive got a 2004 and it was gettn like 14-15 mpg on regular gas, I use hi octane now and im getn close to 18mpg on the hiway, also runnin 305/60/20's on it, i stuck a k&n air filter in but everything else is stock so im happy with its mileage considering

 

It's not recommended to run premium in our trucks unless it's been tuned for it. The manual even says so.

My 5.2 is only getting about 12mpg combined City/Highway so I definitely see a the 5.9 struggling to get to 18mpg.

 

There hasn't been points in the distributor since the mid 70's.........

 

When my truck was stock I got 17 on the highway. 97 ext cab 5.9 4x4 with 265 75 16's and 3.55's. And I'll hook up with a chevy any day of the week lol.

 

Who cares about MPG then, isn't gas like 65cents per gallon ?

 

We were both running 265/75/16's now I'm up to 285/75/16's and I get about 12. I'm not sure how to check what gears he has though?

 

well i guess i will just do a tune up for now and when i get some money in, do a cold air intake, t/b, full length headers and a free flow exhaust...with a splice in for my cat during smog time a tuner for ecm changing so i can get the most mpg when needed and power when play'n around.

Now i know more power usually means more gas but hey i found an article on summit racing saying it can give me better mpg so my pops cant give me crap lol

also is 3.73 and 285/75r16 a good combo? Or would 3.54 be better? i would like to be able to cruise with my rpm roughly 2K

even in bum ****ed egypt the gas is still 3.39 a gal

 

my 03 Ram has the 4.7 for a quad cab with a manual transmission and gets 16 around town and around 18-20 highway. Im very pleased with this for such a heavy truck with 120,00 miles . No complaints but im having some ball joint noise now and pretty sure its needs replacing . This truck has made me a big fan of this era for dodge

 

btw i have a flowmaster with a single side pipe and 17" 245 tires

 

More power doesn't necessarily mean more gas. If you can make more power in your cruising rpm range, you will get better mileage cause its in the throttle less.
It is the reason why putting a major overdrive so you are cruising 60 at 1000 rpm doesn't work (maybe for a diesel).
Performing mods that will give you more top end won't do anything to help mileage.