gas milage help with new tires

[m4dc0w]

A few months ago I went from 235's to 265's, with a 3.73.

I noticed my mielage dropped from approx 350 km per 65L to about 285 km per 65L.

I know the sped is off approx 10% so I have to switch the gear to calibrate it.
The problem I have notice is much higher revs before shifts.

Can the larger tires cause that much of a change in milage? and is it worth reprogramming the computer with bamachips program?

-mc

 

[Nocturnall]

Unless my math is off your milage was cut in half by going up a few tire sizes? Did they install mercury inside the tire before mounting it because that's rediculous.... I THINK that you can reprogram the computer to shift lower but it might put a lot of strain on the drive train. I know it's not recommended to drive around in OD because it strains the trans and engine driving at that low of rpms.