Most customers have a 275 gallon tank that are 5 ft in length,-(slightly larger 330 gallons tanks can measure 6ft in length). Most gauges give an accurate reading of how much oil is in your tank. Below is an estimation of your gauge reading converted into gallons. There are manufacturer differences in tanks so these numbers are approximations.
275 tank 330 tank
• 1/8 = 30 gals 1/8 = 37 gals
• 1/4 = 60 gals 1/4 = 75 gals
• 3/8 = 95 gals 3/8 = 111 gals
• 1/2 = 125 gals 1/2 = 150 gals
• 5/8 = 165 gals 5/8 = 185 gals
• 3/4 = 190 gals 3/4 = 225 gals
• 7/8 = 230 gals 7/8 = 259 gals
• “full” = 250 gals "full" = 300 gals
Please note that tanks that lay on their sides-commonly referred to as “Belly Tanks” have a small variation in gauge estimations.
** A true way to determine the exact amount of fuel in any tank (above or below ground) is to use an oil measure stick and tank chart.