A $4,000 reward is being offered for information leading to an arrest and conviction.
The crash happened around 10 p.m. on Friday, Sept. 13 on the ramp from I-95 North to I-476 North in Ridley Township.
Authorities say someone opened fire on 29-year-old Clinton Martin as he was driving home from work.
State police don't know if it's a case of road rage or if Martin was targeted.
'This is devastating': Family of man shot, killed in Delaware County car crash plead for justice
Martin lost control of his vehicle and hit 33-year-old Joshua Waltz, who was on the shoulder of the ramp.
Waltz, a resident of Odessa, Delaware, was standing near the rear bumper of his car when the crash happened.
Waltz was there, police say, because he had struck debris on the roadway and his car had become disabled.
Both men were pronounced dead at the scene.
Police believe the shooting happened shortly before the crash, and they've determined the shot came from another vehicle.
"The actions by the person that shot at Mr. Martin's vehicle contributed, and caused, the senseless death of two men. Two men that didn't even know each other. Two men that were driving home, going about their own business," said Lt. John Sunderland of Pennsylvania State Police.
Police, family holder news conference after shooting and crash on I-95
During a news conference on Friday, Martin's family members said they were still trying to come to terms with the tragedy.
"We are heartbroken. We are still piecing together that my son is not coming back," said Martin's mother, Constance Newton. "He was a good guy, he was genuinely a loveable guy."
"It's really hard for us. It's senseless. He was just coming home from work, had just finished his shift," said Martin's stepfather, Fredrick Newton.
State police are asking for witnesses to the shooting, or the crash, to come forward.
They are also asking drivers who were near the scene at the time to check their dash cam video for any clues.
Waltz's family has not commented on the tragedy. State police say the family is too distraught at this time.
Anyone with information can call state police at 484-840-1000 or 1-800-4-PA-TIPS.