Lately my 4.8L (all stock) silverado has been getting really bad mileage, it used to get 15-16 or higher city driving, but it now gets around 12-13, almost like a switch was flipped it just got horrible gas mileage. my buddy thought it was a fuel filter, but i read that you had to get a whole new fuel pump on 2004 and up models. not sure what it is but i would like to get it back to the 15-16 mpg asap. any help with this would be lovely. thank you very much and have a Happy Thanksgiving!

 

You just noticed it recently? Like when it started to get into winter? Gas stations switched to winter blend which usually causes a couple mpg loss. I know I was at around 15 hwy and now on my last tank or 12.5 hand calculated. Nothin has changed with codes or anything? How many miles?

 

I realize about a 20% loss in mpg with ethanol bklend over 100% gas.

 

Thanks for the reply, no code or anything, never thought about the winter gas, and yes just around the beginning of November. It has almost 150k.

 

ddog,

About all you can do is make sure your tires stay inflated, and that your air filter is in good condition.

So many things can cause milage to drop. Tune up, more wind, brakes
dragging slightly, driving habits, any load changes, carrying more people.

 

winter blend fuel IMO

 

^ I agree with country. Mileage always drops in the winter.

 

well oh well haha. thanks for the replies anyways guys!

 

IMO, tire inflation, shocks, and the air filter, if

it came on suddenly. All can rob you

of a mile or two per gallon.

Be especially careful of tire inflation during the

cold season.

 

I will check my tires, and the air filer, how would bad shocks rob fuel economy? And do you think a fuel filter would be a cause? And ive heard that they are built in to the pump, is this true? Thanks again