Fred Hunter, of Wilton, crashed just after noon when his Nissan Altima drifted across three lanes of traffic on the Route 7 connector near exit 2 just before the crash, Connecticut State Police said.
He collided with a guardrail, tearing about 100 feet of the metal off its posts and spreading it along the shoulder.
Paramedics pronounced him dead at the scene.
Police are not sure what caused Hunter to collide with the barrier.
Investigators ask anyone who saw the crash to contact Trooper Michael Federowicz at Troop G in Bridgeport at 203-696-2300 or by email at michael.federowicz@ct.gov.
Troopers are particularly interested in finding anyone with dash cam video of the wreck.
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