CHEVROLET ENGINE POOR MILEAGE

I Have A 2009 Chevy Impala. Since Nov. My Gas Mileage Has Been Averaging Between 22-24 Mpg. I Took It To The Dealership And They Say Nothing...

Van Is Rated 16mpg City 20mpg Highway Im Getting Average 12.5 Mpg Which Is 60%highway 40%city.I Also Have A 1999 Astro Same Van Same Engine...

I Have A 1992 K1500 With Low-3rd Gear And Overdrive. I Don't Know The Gear Ratios But They Are Stock. I Don't Need These Low Of Gears For...

I Just Bought A2006 Chevy Express 2500 Cargo Van I Am On My Third Tank Of Gas And Am Getting 7-9 Mpg City Driving Cold Weather But This...

Okay, I Know It's An Old Econobox Car. The Engine Is In Basically Pristine Condition. Doesn't Use Any Oil, Even At 5k-ish Miles...

I Use This Car For Delivery Work A Lot. Yesterday I Put Over 250 Miles On It Delivering. On A Mail Route, With The Heavy Stop And Go, It...