Gas mileage sucks-ideas?

[dagwood2001]

OK....so I do have a bit of a lead foot, and live in a fairly hilly area. That said, I am extremely disappointed in my mileage.

 

I am averaging 14.1 MPG overall, with app. 60% of it being city and 40% highway. I am running 87 octane, and have the 5.3L V-8. Have had the truck for 3 months or so have have about 2400 miles on it. One think I did notice is my tire pressure seems very low, usually reading in the 29-32 range; I am going to the dealer to get closer to 35-36. I know engines and trannies (insert joke here) take time to break in, but in looking at other's MPG figures, as well as what GM is advertising, I seem way, way off.

 

Any ideas on what I can do to improve my mileage? Everything is stock still, haven't flipped tires, heck I haven't even sprayed the bed yet. I've also tried a few different gas stations and nothing seems to change. With the potential for a massive (.25-.30 cent per gallon) tax increase coming here in PA, I'd really like to address this. I will talk to the dealer about it of course, but curious if anybody is/was in the same boat and what they've tried and if it worked.....

[stillingsl]

I have definitely noticed that having 35 psi at cold on my tires greatly improves my gas mileage. I have 6000 miles now and am average just under 20, which includes towing smaller trailers for 1500 of those miles. I have the 5.3 w/ 3.42 rear diff. My best in 60+ degree weather is 23 mpg ave over 400 miles according to the truck, which I have verified is pretty close. Between fill ups.

[TimmyG]

My mpg got better and better till 7500 miles or so

 

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[TimmyG]

I have 40, 000 miles on my 5.3 crewcab 4x4. I avg 17.1 hand calculated. With my front air dam removed and 3in bodylift. It was more along 18ish before the lift

 

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[redwngr]

What pressure does the door sticker recommend for your truck?

[MotoMedic]

Recommended pressures are only general figures.

Higher pressures = increased MPG, but they also mean a rougher ride. If you decide to go above 40psi be sure to keep an eye on tire wear... if the center is wearing faster than the edge the tire is overinflated!

Factory MPG figures are based on a flat 'road' so your options are to either drive more conservatively or move to a hill free town.

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