Weight of Diesel Fuel and What it Means for Truck Drivers

Fuel – it’s the juice that keeps trucks running. If you’re going to haul loads to keep your trucking company successful, you need diesel fuel to get you from pickup to delivery.

How much does diesel fuel weigh? It’s a simple equation, but have you ever stopped to wonder the details of diesel fuel? What about the fuel weight of a full tank of diesel on a semi-truck? Does diesel weigh more depending on the outside temperature? How does that weight of diesel fuel impact your truck weight, especially when it’s time to hit the scales?

Don’t you worry, we have answers to those questions and more.

How Much Does a Gallon of Diesel Weigh?

The weight of diesel fuel is about 7 pounds per gallon. Diesel weighs a little less than 7 pounds per gallon in the US (and a little more than 7 pounds per gallon in Canada), but let’s go with 7 pounds per gallon to make it an easy number. 

What is the weight of a full semi-truck fuel tank?

Semi-truck fuel tanks do come in varying sizes, but they hold an average of 125 to 300 gallons of fuel. A fuel tank sits on each side of the tractor and fuel is distributed between the two tanks to balance the truck’s total weight. So, since diesel fuel weighs about 7 pounds per gallon that means that a full tank of fuel weighs anywhere from 875 to 2,100 pounds.

Do you have a smaller diesel fuel tank? It will be pretty easy to calculate. If one gallon of diesel weighs 7 pounds, 100 gallons of diesel fuel weighs about 700 pounds. 50 gallons of diesel fuel weights about 350 pounds.

Does the weight of diesel fuel change when it’s colder vs. warmer?

Yes, but it’s really a super small amount. Check out this fuel weight calculator. So, let’s say it is 16 degrees Fahrenheit, one gallon of diesel fuel weighs 7.1 pounds. Now change it to 106 degrees Fahrenheit and the same gallon of diesel fuel weighs 6.8 pounds. Now, go to a quite comfortable temperature of 70 degrees Fahrenheit. That gallon of diesel fuel weighs 6.9 pounds. See? The differences are all very minimal. Think of it this way: The temperature weight difference of diesel fuel will never be more than 10-50 pounds depending on the size of the fuel tank.

What to do Before the Scale

Should you fill up your tank before the weigh station?

You should always factor in the amount of fuel you are carrying before you hit the scales. If you have 100 gallons of diesel in your tank, then that’s about 700 pounds that’s added to your truck weight. It’s good to mentally overestimate your truck’s weight, so that when it sits on the scale it remains within weight limits. Otherwise you might be faced with a ticket for being over the weight limit.

What are the truck weight regulations?

According to federal law, single axles are limited to 20,000 pounds, axles spaced between 40 inches and 96 inches apart (tandem axles) are limited to 34,000 pounds. The gross vehicle weight is limited to 80,000 pounds. For safety reasons, different jurisdictions might have different rules for large trucks, so be aware of the rules where you are driving.

Saving money on diesel fuel, and on truck service and maintenance, is important for all truckers and trucking companies. That’s what the TCS Fuel Card can do for you. Are you ready to save on fuel? Get a TCS Fuel Card today!