Getting more mileage out of '01 Suburban?

[93YukonSLE]

My best friend has a 2001 Chevrolet Suburban, 2wd, 5.3L. He's looking to increase his mileage, right now he gets about 16 city. The only mods are 265/70R17 wheels and tires off an '07 Tahoe and a 3" Jardine cat-back exhaust system. Is there a custome tune he can get to increase gas mileage instead of performance? Maybe a good CAI to gain 1mpg, maybe more? I checked out westers and they did not offer anything for the suburban. Thanks in advance.

[Alex D]

I think 16 mpg city is darn good for that truck. I mostly get 14 with 20 on the highway (17 mixed). Questions should be: is it realistic to expect better. I think the easiest way besides a CAI is to be easier on the go-pedal.

[Pauly]

I also think that 16 city is pretty good mileage in a truck, esp a Burb.

peace
PAuly