Your 2017 Ford F-150 is designed to operate on regular unleaded gasoline with a MINImum pump (R+M)/2 octane rating of 87 or regular unleaded gasoline blended with a maximum of 85% ethanol (E85).

Older cars can run on unleaded gas, but avoid ethanol.

Using regular gas in an engine that requires premium could void your warranty. “Use premium unleaded gasoline with a posted octane rating of 91 or higher. If the octane rating is less than 91, you could damage the engine and may void your vehicle warranty.

Unleaded gasoline was introduced in the 1970s when health problems from lead became apparent. In the United States, leaded gasoline for use in on-road vehicles was completely phased out as of January 1, 1996. Most other countries have also stopped using leaded gasoline in vehicles.

The Public Health Service held a conference in 1925 to address the problem of leaded gasoline. Tetraethyl lead would tend to clog up these converters making them inoperable. Thus, unleaded gasoline became the fuel of choice for any car with a catalytic converter.

Leaded gasoline was the primary fuel type produced and sold in America until 1975. Although Time magazine in 2010 called leaded gas one of the 50 worst inventions of all time, it’s still sold in the U.S. for use in off-road vehicles, farm equipment, aircraft, race cars, and marine engines.

But remember – if your engine needs an unleaded fuel, you don’t want to mix leaded with unleaded. Doing so would make a leaded fuel which could still damage oxygen sensors and catalytic converters. The percentage of the 100 octane fuel in the mix is 2/5 = 0.40 ( 40%).

Leaded ‘four-star’ petrol was withdrawn from sale in 2000 and the product that replaced it – Lead Replacement Petrol (LRP) – went the same way in 2003 as sales were so low. If you’ve got a pre-1992 car it’s important to find out if it can run on normal (95 octane) unleaded petrol.

A classic car specialist has warned drivers should use the more expensive premium grade unleaded fuel now and again because it is good for the engine. Mark Knight, Director of classic car specialists at Retro Marques has urged drivers to use the more expensive fuel “every third or fourth tank” where they can.

If moist air gets into the tank, the ethanol will absorb the water and can lead to running problems and rust. Ethanol can also corrode fiberglass and rubber, often found in classic cars. To keep your classic car in great shape, we recommend filling it with non-ethanol gas.

The higher octane gives premium gas greater resistance to early fuel ignition, which can result in potential damage, sometimes accompanied by audible engine knocking or pinging. But if the vehicle manufacturer says your engine needs only 87-octane regular, that is what you should use.