Prerunner Gas Mileage

My 2004 4x4 double cab is getting 16 city & 20 highway.

You need to get about 10k on it for tollerances to open up a bit --- then mileage will improve. Suspect the advertized mileage is with premium even though you can use regular. Using regular force the computer to retart timing reducing performance and mileage. Add another 3-4 psi of air to your tires too.

Suspect the advertized mileage is with premium even

Here is something that I have often questioned, The claim that using higher grade gas has any influence on your millage i was always told that it was a load of SH*T that using higher octane gave you better millage, - and that was from my boss when I worked at a full service station about 12 years ago. My understanind was that octane only helped with pinging. without saying the poster above is wrong, Am I off, or is the idea behind higher octane = better millage a load of crap??

Dave

Sounds like you have a heavy foot. My Prerunner x-tra cab has always gotten

My '03 4Runner V8 get 15/19.

Thanks for the responses. Looks like I need to have the dealer take a look at it. In addition to the poor gas mileage, I'm also getting poor performance while going up the mildest inclines. If feels like I'm running a 4 cylinder with a heavy load.

New vehicles are controlled by elctronic computers that vary the timeing to eliminate knocking or pinging. So yes 12 years ago premium was used to eliminate pinging and was pretty much wasted if engine was not all carboned up on inside. It is no longer true.

Just bought a '02 Tacoma double-cab V-6 on Thursday. It came from original owner with 19k miles on it. Have started a gas mileage check. I'm going to do it somewhat carefully by using the same gas pump each time so that the "shut-off" point is the same. Sure, it averages out over many fill-ups, but what the heck.

Also, I read that on very hot days the air is about 17% thinner than on very cold days and that can have an impact (literally) at freeway speeds. (point is: all the test conditions are important)

-Steve

z> Sounds like you have a heavy foot. My Prerunner x-tra cab has always gotten