I usually get 260 before the light comes on. I still have 2.5 gallons when that happens though. Roughly 17-18mpg.
Also remember with bigger tires if you have not recalibrated your speedo, the odometer does read right. It will say you've only gone 220miles where as you really have traveled 260miles. Get what im saying.
at one time, when i had 31's i got 300+ out of a tank, since i lifted and put 33's on i only get 220 at best, i didnt think that this would be sooo dramatic, i also was getting 260+ when I first put the larger tires on, and i cant change the o2 sensors because the jackass that owned the truck before me stripped out the bolts, so i guess if any one can help out with that....please do!!!
I routinely get 340-360 miles per tank. Taco extra cab, 5" lift, 265/70r16, 3.4L. Before the lift, I got about 22 mpg. I do alot of highway driving, 100 mi. commute. I fill up every three days. Since gas prices went up, I try to keep it at 65 mph.
Over the last year and half I have averaged 18.4 miles per gallon. Low of 12 mpg, high of 24 mpg. The truck is totally stock except for a K&N filter and elbo mod. That works out to about 330 miles to a full tank. But that would be all 18 gallons. So if we assume that there are 2.5 gallons left in tank when the light come on, It would be getting around 285 miles to a tank.