It happened Wednesday evening on I-57 near the town of Onarga about 30 miles from Kankakee.
Eighty-year-old Jack Douglas of Bartlett stopped to help Jimmy Lee Westbrook from Tennessee.
Westbrook was killed when he went to retrieve the tire. Douglas crossed the street to call for help and was also hit by a vehicle and died.
Douglas's family says his extraordinary act of kindness reflects his humble nature.
"He stopped, because as far as paying it forward -- people were kind so him, so he would do the same thing," said son-in-law John Babowice. "The trooper had actually called him a hero. He says people very rarely stop."
So far there have been no charges filed in either accident.