Greetings! Just joined and pretty excited cause this looks like a very active forum.

I recently bought a 2007 Silverado Crew Cab with the 4.8L engine. I can't seem to get above 16MPG regardless of how I drive it. The reason I got it is that a few people I've run into told me they got up to 20 MPG on the interstate. My mom's 2002 Suburban 5.3L did the same thing while her 1997 5.7L she use to have would EASILY get up to 18 and 19 MPG.

Does my truck have a problem? Or is this normal?

Everything's stock (air intake, exhaust, etc.) and it runs great (no leaks of any kind).

Thanks for the help!

 

that is probably pretty average with just stock but if you wanna get it better try the little things better air filter(material filter not paper) throw a bottle of fuel system cleaner in the next time you fill up. i put a k&n on my 97 5.7 and if im going 50-65 mph i get about 21-23 mpg and i just have the little add ons the get a little extra but it helped me out about 6mpg

 

I have a 11 silverado 4x4 with a k&n cold air box and the best I have ever gotten was 15.9 on the highway. So i think were just stuck with it.