Try Running some BG 44k Through your system. That should help

 

See that's were the companys get ya. Once you do all these installs you wanna keep your foot on the gas an you don't notice a thing.

 

When I bought my '03 Hemi with 113,000 miles in Apr 09 it was reading 12.9 on the overhead display and I watched the needle move pretty quickly towards E. Replaced original plugs, installed CAI, replaced faulty gas cap, replaced front and rear gear lube with good synthetic stuff (can't remember the brand), the oil was black so I have changed it 3x in 5000 miles with the last 2x adding a quart of Rislone to clean the motor internally before I switch to synthetic motor oil. Anyway, the gauge now reads 19 mpg which is 70% highway and 30% city. Exhaust is a dumped turbo in front of rear axle. I am really pleased with this truck.

 

I get about 18 mpg avg. with a stock 2008 1500 5.7 hemi, it was better when new around 19.5 mpg. The rear end went out at 13,000 miles and it hasn't got the same since.

 

I have hit 27 MPG downhill at 75mph...So I don't haha. That MDS really does wonders on flat ground. When I bought my truck, I was doing 19 on the highway, and 15-16 in the city. However I think somethings wrong now cause i'm not doing that anymore. I know its possible tho.

 

Truer words have never been typed Can't seem too let up even for a little trip. Gotta blast a corner or two. Then let's not forget mister WOT! Gotta see if nhe's home today. lol Real hard too stay off that pedalo. After the mods anyway.