5.5 gal → V (L) Solve the above proportion to obtain the volume V in liters: V (L) = 5.5 gal × 3.7854118 L. V (L) = 20.8197649 L. The final result is: 5.5 gal → 20.8197649 L. We conclude that 5.5 gallons is equivalent to 20.8197649 liters: 5.5 gallons = 20.8197649 liters 5 gallons is equal to about 18.9 liters. In Scientific Notation 5 gallons = 5 x 10 0 gallons ≈ 1.89271 x 10 1 liters Gallons Liters A liter, or litre, is a unit of volume in the metric system. A liter is defined as the volume of a cube that is 10 centimeters on a side. There are about 3.785 liters in a U.S. gallon. Abbreviation: L To convert 5 Gallons to Liters you have to multiply 5 by 3.7854118, since 1 Gallon is 3.7854118 Liters. The result is the following: 5 gal × 3.7854118 = 18.927 L. 5 gal = 18.927 L. We conclude that five 5 Gallons is equivalent to eighteen point nine two seven Liters: 5 Gallons is equal to 18.927 Liters. Therefore, if you want to calculate how akw1uy.