Hydroplaning Beside a Tractor-Trailer
You are driving a 2012 sedan on the New York State Thruway at 65 mph in a 65-mph zone. It has been raining hard for 20 minutes, and standing water is about 1/8 inch deep in the right lane. Your tires have 4/32 inch of tread; the legal minimum is 2/32 inch. Cruise control is set at 65. A tractor-trailer is in the lane to your left. Its trailer tires throw spray that cuts visibility to about 150 feet. You feel the steering go light, and the engine revs rise slightly as the front tires lose contact with the pavement. The road curves slightly to the right. Traffic is moderate, and the shoulder is narrow with a guardrail. What do you do?
1. What is happening, and what are your immediate actions?
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The front tires have lost contact with the pavement and are hydroplaning on the standing water. The light steering and rising engine revs are clues. Ease off the accelerator smoothly and hold the wheel straight. Do not brake hard and do not steer suddenly; either can cause a spin. Disengage cruise control with the cancel button rather than a hard brake tap. Wait for the tires to regain contact, then slow gradually. After recovery, reduce speed to about 45-50 mph and increase your following distance.
2. Why are cruise control and the truck's spray especially risky here?
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Cruise control tries to maintain 65 mph, so if the drive wheels slip it may add power and make the hydroplaning worse. That is why it must be switched off at the first sign of lost traction. The truck's spray cuts visibility to about 150 feet and puts you in the trailer's no-zone, where the driver may not see you. If you drift while hydroplaning, you could move into the truck. Drop back out of the spray rather than riding alongside. With only 4/32 inch of tread, your tires clear water poorly; slow down more than you would with new tires.
3. What should you do after the car regains traction, and what maintenance issue matters?
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Keep both hands on the wheel, scan far ahead, and avoid puddles and sudden lane changes. Use low beams, not high beams, in rain, and leave at least 4 seconds of following distance. Stay below the speed at which the car feels light. The maintenance issue is tire tread: 4/32 inch is legal because the minimum is 2/32, but wet traction is already reduced. Plan to replace the tires soon and check pressure. If the rain is too heavy or the car feels unstable again, take an exit and wait.