sucky gas milage?

Question

i own a 04 serria i get about 14- 15 miles per gallon on the highway truck has 80k miles i have changed oil and filters normally i asked the dealer i bought it from they say "its a truck" but the truck i traded in was a 99 with almost 200k miles and got about 25 mpg and my step father has the same truck and gets close to 30 mpg on the highway i get as low as 10 in town truck runs fine i dont put my foot in it any other ideas

worst gas milage i ever got in my 99 sierra was 13 mpg towing a box trailor all weekend in a snow storm in 4x4 my cousin owns a ford v10 and gets better mileage than i do

and yes they are all three ( my new one my old one and my step fathers ) trucks are the same all factory same motor body style drive train tire size ect and have kept the filters changed never thought about the brakes hanging up

Answer 1

There's many things that can affect gas mileage. Make sure it's tuned up. and the filters are good. You can get some spray stuff to clean your throttle body. Go to your favorite auto supply and purchase some throttle body cleaner. Remove the air cleaner.Have a friend hold The gas pedal to the floor (car not running) and spray until all the black stuff is gone. There is also a spray cleaner for your MAF sensor, that might help. Worst case is that your catalytic converter might be a little blocked. This will affect gas mileage as well as power. That can be checked by removing the O2 sensor and putting a pressure gage in the O2 hole. Over sized tires can drop mileage. One more thing, go on the freeway and check your speedometer against the mile markers. 60MPH is easiest. Maybe your speedometer is off and you're not getting as rotten mileage as you think you are... Also, sometimes people exaggerate their gas mileage, I think it's kinda like fish stories.

Answer 2

Are we talking apples to apples?? or does your truck have a bigger engine? Does this truck have "overdrive transmission" (same as others"") Are you runing "fat ovesized tires" as compared to the others! Are your brakes running free?? (jack up truck and see if wheels turn without a large amount of resistance)! Is your air cleaner element clean,- dirty one can make truck run ok,but working like driving with choke on! Are your tires the right circumference?? bigger tires may make you speedometer work way off (like for instasnce 32" tires against 20' tires)!

And then there is the "jinx" factor some trucks just don't get the same mileage truck ro truck! Does your truck get similar miles to one of the same year- with same options and engine transmission setup! Sometimes a year model just won't get the mileage it should in any of the trucks produced that year!

I have an 83 Chev 1/2 ton that I would love to get 11 mpg out of! .. it gets more like 6! However It is a $500 truck, and I don't have money to buy a much newer one, so I'll drive as little as possible on 6mpg and live with it for a while. You know!! --I can drive a lot of miles on $6,000 worth of gas - even at $3 a gallon!

Answer 3

The only truck I have ever seen get 25 or 30 miles per gallon was a 4 cylinder 5 speed standard Ford Ranger and oh yeah an Isuzu Diesel which got 40 to 50 MPG. If you're getting that kind of mileage with a full size truck you're either driving all downhill or the speedometer is really out of whack or you don't know how to figure gas mileage. There just aren't any full size trucks out there that will get that kind of mileage. I wish there were. I'd buy it in a heartbeat.

Answer 4

remove the vacuum hose to the fuel pressure regulator and make sure there is no fuel present, if it is dry have someone with a scan tool check your oxygen sensors for proper activity, also check for vacuum leaks

Answer 5

have it Checked for vacuum leaks
old hoses do crack