The fire broke out in the eastbound lanes by Smith Road in Parsippany around 7:10 a.m., the Parsippany Troy-Hills Fire Department said.
Photos from the scene show a UniFirst uniform rental company truck billowing with flames and smoking heavily.
Crews worked for more than an hour to fully douse the blaze and the surrounding hotspots.
Two of the three left lanes were temporarily closed west of Exit 45 to Route 637/Beverwyck Road, according to 511NJ.
No injuries were reported, the department said.
The cause of the fire was not immediately clear.
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