In one incident, nails spill out onto the highway, damaging more than a dozen cars.
In another, plywood flew off a vehicle and smashed through a windshield.
Drivers told Action News they were traveling on the Schuylkill Expressway near Montgomery Drive on Tuesday when their tires suddenly popped.
Pennsylvania State Police said during rush hour, around 5 p.m., a load of nails fell off a truck and spilled onto the highway. Police say as many as 15 cars were damaged.
"That was definitely the scariest place I've had car trouble," said Nakoa Salna, of Roxborough.
Salna was one of more than a dozen drivers stranded on the shoulder after driving over nails.
"Even after I drove over it, I didn't know that they were nails right away. It wasn't going to be avoidable with that much traffic," she said.
"This seems like a freak accident," said AAA spokesperson Jana Tidwell.
AAA got several calls from drivers and says technicians often end up towing vehicles because people don't always realize some cars don't automatically come with a spare tire.
"With manufacturers not making them standard in many new vehicles to make the vehicle more fuel efficient, it's an add-on. It's extra, it costs extra money," Tidwell said.
Tidwell said something people can take away from this situation - check to see if you have a spare in your car. She said many car manufacturers aren't including a spare tire in their newer models.
In a separate incident on I-76, a spare tire wouldn't have helped a father and daughter Saturday morning.
Father and daughter unharmed after unusual accident on I-76
"It was just kind of an instantaneous smash and there was wood all over glass all over" recalled Gianna Scarpa.
Kevin Scarpa was driving his daughter, Gianna, back to Arcadia University for her junior year when the unexpected happened.
"I saw a piece of plywood from the car flip over and then the windshield instantly exploded, and we were covered in these pretty small shards of glass," Kevin said. ""Didn't even have time to touch the brake. We were still doing 65 mph with no left view mirror, rear view mirror and a white windshield."
Despite the damage, Kevin managed to safely pull over to the side of the road. The vehicle carrying the plywood continued driving westbound and did not stop.
"I didn't even have time to look for their license plate. I just know it was either white or silver. It was a four-door SUV, but that's all I know about it," Kevin said.
The Scarpa family is hoping someone saw the other vehicle just so they can get insurance information.
Pennsylvania State Police are investigating the case. The Scarpas say they are not interested in pursuing legal action but hope to identify the driver for insurance purposes.