Tank trucks are used a lot like rail cars are, but they will usually transport refined fuel to a fuel station, like a gas station. Trucks are usually used to carry smaller capacities of oil short distances. Like railcars these trucks can carry several different forms of this petroleum, but they do not really carry the petroleum in its crude oil form because it would take a lot of trucks to deliver the volume of crude that the refineries demand. These trucks can deliver this fuel to gas stations, or deliver the fuel straight to the consumer. These trucks are used in situations where it would be illogical to use railcars, pipelines and tanker ships. Places like gas stations; that are not able to be accessed by marine vessels, and do not demand the volume that is delivered by pipelines or trains, would get their fuel from tanker trucks. This allows a rational and cost effective way to deliver the fuel to the consumers through the gas station. Common sizes range from 400 up to 7,500 US gallons.
A tank truck or tanker truck (United States usage) or tanker (United Kingdom usage), is a motor vehicle designed to carry liquefied loads, dry bulk cargo or gases on roads. The largest such vehicles are similar to railroad tank cars which are also designed to carry liquefied loads. Many variants exist due to the wide variety of liquids that can be transported. Tank trucks tend to be large; they may be insulated or non-insulated; pressurized or non-pressurized; and designed for single or multiple loads (often by means of internal divisions in their tank). Some are semi-trailer trucks. They are difficult to drive due to their high center of gravity.