Just filled up again. 14.5mpg on this tank but I didn't drive conservative and I towed a bit.

I used 89 octane and two bottles of STP super concentrated Fuel Injector cleaner (since 1 bottle treats 21 gallons). I'll see if it makes a difference.

 

since it is high mileage you might look into when the last rear end and tranny service were. If it has not been done in a while it definitly needs it and synthetic fluids would probably give you a slight increase in economy as well as be easier on your parts.

 

the higher octane burns easier, so it won't leave as much residue, it ignites faster and burns more thoroughly. btw dont worry about the octane booster if your engine isnt pinging, and the "mileage booster" is just snake oil in a gas engine

 

the higher the octane the more resistant it is to combustion due to compression instead of the spark. In an engine like ours this is not a big deal since the motor was designed to allow for a certain amount of this without knocking whereas in a performance engine with higher compression and more aggressive fuel and timing curves this allowance for premature combustion is not allowed for so higher octane fuels must be used. The higher octane fuel will give you better combustion and put less stress on the motor like 7m said and better gas mileage could result, but if there is any gain it probably will not be noticible.

 

wich says what I just said. That is why most certified mechanics will recommend the use of higher octane gas on older vehicles.

 

Ha Ha you got suckered in like rest of us thinking 3.7 would get better MPG.

Grin and take it like a man cry alot you not the only one who got stuck with a under powered not so good MPG truck I just waiting to pay my way down or off before I get rid of this truck Like the Truck but MPG sucks and having no power on top of it makes this a truck which I not planning to keep.

Oh yea don't waste you money on extras trying to improve it been down that road not worth the money you going to spend and what you get out of the truck just drive it.

If you are going to spend money on the truck the Anti Sway bar is the best bang for the buck.

 

I have had the same problem here lately, except mine is an 06' ram 1500 3.7L V-6. I used to be able to top off the tank, until I couldn't put any more gas in, and it would stay above the full line for at least 4 or 5 days without going down, now, I drive 2 days just to and from school, and it goes down. i am now putting 10 or so bucks in every other day to keep it full. ( I dont like to run the gas down to far) trucks only got a bit under 17,000 miles on it.

 

start reading at post number 28 here:

https://dodgeforum.com/forum/showthr...t=56153&page=3

it is a very long read.

notice that some of the mods not only improve MPG
but also improve torque
which will make driving your 3.7 'feel' better

in a nutshell
you want to educate yourself about 'HyperMiler' like driving
reduce your tire's rolling resistance
make your truck slip through the wind easier (aerodynamics)

the newbie mistake is to try to improve the engine first