increasing fuel efficiency

When I bought my Tahoe, I was well aware of the horror stories of poor gas mileage. I purchase a K&N stock replacement filter to help the gas mileage, but it only seemed to get worse. Of course, I used 89 octane the past two times rather than 93 octane, but would that make a 3mpg difference? Does the K&N FIPK increase gas mileage on an '04 Tahoe? Any other suggestions on increasing miles per gallon will be greatly appreciated.

I don't know why you would use anything above 87 octane - with a compression ratio of less than 10:1, the high octane fuel really isn't doing anything for you.

I recently read that it will take the computer about a month to "adjust" to the new K&N stock replacement filter. Is this true?

I use 93 Octane but das cuz I I got Superchips. And yes I can feel the diff between 87 n 93. Same fuel consumption tho.

What poor gas mileage. If you check out other 4x4 and SUV's I think that once you look at the numbers the Tahoe looks pretty good. There are some V-6 SUV out there that barely get better. Check out this site and you'll see what I mean.

http://oee.nrcan.gc.ca/transportation/tools/fuel-consumption-guide/fuel-consumption-guide.cfm?attr=8

For example Chevrolet Tahoe 22mpg highway 5.3L V-8
Nissan Pathfinder 24mpg highway 3.5L V-6
Toyota Sequoia 22mpg 4.7L V-8

you got superchips and you are worried about gas milage?????