Emergency crews battled the raging blaze for three hours after the 8 a.m. accident Saturday between Melville and Plainview near the Nassau County line.
The intense heat melted the supports for a huge road sign, which collapsed across all eight lanes of the roadway. Heavy equipment was brought in to remove it.
The westbound lanes reopened about 6:15 p.m.
Authorities were still uncertain when eastbound lanes of the heavily trafficked highway might reopen. The accident caused the pavement to buckle.
Authorities have identified the driver as 57-year-old Mujahid (moo-jah-HEED') Shah of Brooklyn.
