Dude...if every time I was running out of gas I turned off and got ass...I would put a switch on that light to make it come on more! Use the trip. On the highway you can safely get 120 miles before the light. That should leave you 25-30 miles. Get gas at 120 and dont worry.
I can get 180-200 Miles per tank depending on how big my balls are that day. That is with a 14T front. One thing to remember while using the trip is watch when your light comes on. Mine comes on at about 150Mi... that means I have 50 to go safely. But one time I was going 100 for hours straight. The light came on @ 125 then I ran out of gas @ 170 Miles That 3 Mile push thought me to respect MPG vs. MPH.
Just be smart with the trip and you don't have to waist your time with a gauge.
Edit : To find out tank range just look at how much gas you had left when you fill up. (Sv's will get about 50MPG) :wink: