Fuel gauge

[Blizzard96]

My fuel gauge is acting differently, for the past two years when I fill up it would go way past FULL and I would usually see these miles at these marks:

Right on the FULL Line = 100 miles
3/4 = 200 miles
1/2 = 250 miles
1/4 = Usually around 300

I use my PDA program to calculate my mileage and its usually around 25-26.

The other day I refilled and it went below full after only 50 miles...thinking it was weird I refilled a day or two later and at 120 miles it only took 4.5 gallons which calculated to 27 mpg since I only did highway driving those days.

Maybe I'm worrying too much but I'm just used to my old gauge. :(

[Blizzard96]

Someone at my work mentioned that maybe since the last two times I've refueled it has been during the daytime that the car isn't filling 100% since its hot thus the gauge not going all the way to the most full reading? I usually refuel at night time...*shrug*