(AP) — The options Nebraska drivers find at the gas pump are changing because of a shift in the fuel supply.

Nebraskans have been accustomed to the mid-level 89 octane fuel with ethanol being the cheapest option. Now the regular 87 octane fuel will generally be cheaper.

The change is being happening because oil companies have switched what fuel they pump into terminals in Lincoln, Omaha and Doniphan. Instead of bringing in 87-octane fuel, the oil companies are delivering 84-octane fuel.

University of Nebraska-Lincoln Extension educator John Hay says either ethanol or premium gas is mixed with the lower octane fuel to make the 87- and 89-octane fuels offered at the pump.

Hay says most cars will run fine on 87-octane fuel, but drivers should check their owner’s manuals to be sure.