The fatal victim has been identified as 59-year-old Louis Davis of Philadelphia.
The crash occurred just after 11:30 a.m. on I-76 between Gulph Mills Road and Route 202.
Police say it began when two vehicles, a Ford F-150 and a Nissan Murano, decreased speed behind congested traffic on the Schuylkill Expressway.
That is when, police say, a tractor trailer followed too closely for the existing congested conditions. The driver attempted to stop and swerved from the right lane to the left.
While doing so, the tractor trailer rear-ended Davis' 2007 Dodge Caliber.
The two other vehicles were also involved in the crash.
The drivers of the F-150, Murano, and tractor trailer were injured.
Ariel Froumy was among those involved in the crash. Her Ford F-150 suffered only minor damage thanks to her quick thinking.
"All I saw was the blue tractor trailer coming. I just tried to speed up and move to the side of the road. That's all I remember," Froumy said.
So far there is no word on charges.
"It is a fatality so, per law, a blood sample will be taken of that driver so we can find out, so we can make sure, there is no foul play or anything like that going on," Trooper Danea Durham of the Pennsylvania State Police said Friday.