It happened around 4:40 p.m. Wednesday, Sept. 7 in Melville.
James Dawson, age 52, of the Bronx, was driving a Ford E350 van westbound, just west of Exit 49, when his vehicle struck the center median, Suffolk County Police said.
Dawson was transported to Plainview Hospital where he was pronounced dead, according to police.
Detectives believe Dawson suffered a medical event prior to the crash.
The westbound lanes were closed for around two hours following the crash.
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