Walker was a passenger in a Porsche a friend was driving when it hit a pole and burst into flames in November 2013.
US media report that a wrongful death case has now been filed by Walker's daughter Meadow, who is 16, alleging the carmaker took safety shortcuts.
Porsche has not yet publicly responded to the claims.
After a four-month investigation, police said the Porsche Carrera GT, driven by Walker's friend Roger Rodas, was travelling at 94mph (151kph) in a 45mph zone when it hit a lamp post.
The lawsuit contends that the car was travelling much slower when it went out of control, according to TMZ.
The website, quoting legal documents, says his seatbelt "snapped Walker's torso back with thousands of pounds of force, thereby breaking his ribs and pelvis," and trapping him when the vehicle caught fire.
According to the Los Angeles Times, the document claims the car lacked "features that could have prevented the accident or, at a minimum, allowed Paul Walker to survive the crash".
Meadow Walker has not commented.
Mr Rodas' widow filed a similar case last year, but Porsche said the crash was his fault, rather than down to design flaws.
The daughter of the late Fast and Furious actor Paul Walker is to sue carmaker Porsche over the crash in which he died, US reports say.