Q: Is there a law requiring owners of pickup trucks to adjust their headlights when they put on those big tires? If not, why not? When people jack up their pickup trucks, it makes it hard on other drivers when they pull up behind them at a stoplight. Their “raised” headlights shine into the rearview mirrors of the cars in front and make it almost impossible to see.

A: As long as the height of those headlights are no higher than 54 inches from the ground — 41⁄2 feet — and no less than 22, that big-wheeled pickup truck would be in compliance, said Sally Ridenour, an Oregon Department of Transportation public information officer.

Federal law specifies those measurements, she said, but that doesn’t always prevent other drivers from getting blinded by the light.

“If you are in a Mazda Miata, which rides very low to the ground, and there’s a semitruck behind you, than those lights might be in your rearview mirror. You might need to adjust your mirror so that you can still see behind you, but the lights are not glaring,” Ridenour said. “Most people have experienced that glare in a rearview mirror, especially at night or in the rain from time to time.”

If the glare is too bothersome, drivers on both sides of the light can help each other by maintaining a safe distance apart, Ridenour said.

She noted that a vehicle would have to have extremely tall tires to raise its headlights past 54 inches. Those types of trucks are more likely to be found in a monster truck show than on a road, Ridenour said. And those specialty vehicles are not street legal.

Regarding whether headlights can be adjusted, Ridenour said it would depend on the vehicle and how its lights were mounted.

— Staff Writer Jessica Musicar