There were no obvious signs the 17-year-old driver who crashed into NY Jets legend Dennis Byrd was drunk or texting at the time of the fatal crash ... law enforcement tells TMZ Sports.
50-year-old Byrd was killed when a Ford Explorer slammed into his Hummer H2 at 11:16 AM in Oklahoma on Staurday.
Cops say the driver of the Ford was a 17-year-old boy -- who had a 12-year-old passenger. Both boys were hospitalized in stable condition.
Investigators believe the 17-year-old veered across his lane and into oncoming traffic -- colliding with Byrd's car ... and killing him.