PIERRE, S.D. (AP) - State officials say motorists and gasoline retailers should remember that South Dakota law now limits where 85-octane fuel can be sold and requires cautionary labels on pumps that dispense the low-octane fuel.

The law that took effect in March requires that pumps selling 85-octane fuel must carry a warning label that says the octane level may not meet minimum specifications by vehicle manufacturers.

The law also limits the sale of 85-octane fuel to nine western South Dakota counties. Gasoline sold in all other parts of the state must have a minimum octane rating of 87. Many engine manufacturers recommend a minimum of 87-octane fuel.

The nine counties where 85-octane gasoline can be sold are Butte, Custer, Fall River, Harding, Lawrence, Meade, Pennington, Perkins and Shannon.

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