So my 2010 ram 2500 with the hemi is my daily driver. I'm running 18" wheels with 295/70r18 nitto Terra's. Nitto rates them as 34's. My gas mileage is pretty bad 9-12 combined city/ hwy. I'm thinking about dropping down to stock size, 275 or 285/65r18's to hopefully get closer to the mileage I got when stock which was like 12/20. I do have a heavy foot so that is also to blame. Any thoughts or experience doing the same?

Another idea was removing the AFE intake and putting the stock system back on which I kept.

 

Might also want to check into the weight of your non stock wheel tire combo as compared to the stock setup. Rotating mass is a mileage killer.

 

You'll never go wrong having a well tuned stock system on your truck. Keep those tire on the high side of rated tire pressure to help out with the fuel economy.

 

fyi i read somewhere the CAI does nothing for the Hemi, something to do with automatically adjusting. makes a cool sound though. heres a tire chart for you

http://tire-size-conversion.com/tire...version-chart/

 

I put the stock air intake back on my Durango R/T before selling it and found that the gas mileage increased by 1-2 mpg. Smaller tires and stock intake should help a lot.

 

Ain't that the ugly truth. I do believe there are some LRR tires made for the Ram that will also help out.