Fredy Alexander Amaya died from a gunshot wound to the head, according to the Harris County Institute of Forensic Sciences.
READ ORIGINAL REPORT: Person shot to death inside wrecked vehicle on Sam Houston Tollway at I-45, deputies say
His family, who called him Alex, are devastated by the loss.
"Everybody is shattered. Everybody is heartbroken. We can't find any understanding of why someone would do such a senseless violent crime to someone who was so peaceful and kind to everybody," his brother, Daniel Amaya told ABC13, from his home in Virginia.
He and his family are traveling to Houston on Saturday to make funeral arrangements.
"It shouldn't be like this. He was a good person. He didn't deserve this," Daniel said.
Alex was found shot to death inside his car on the ramp connecting the North Beltway and the North Freeway northbound at about 6:30 p.m.
First responders were dispatched to a single-car crash but discovered a murder.
Houston police told his family they are investigating it as a possible road rage, Daniel said.
"He didn't like to violate the law. He really drives the speed limit and I'm thinking if it was road rage, maybe someone got upset because he was driving too slow," he said.
Amaya said his brother had just gotten off work.
His red Volvo, which he proudly shared photos of when he bought it last year, has five bullet holes.
Houston police have no suspect description, according to a press release.
The 46-year-old was a kind and hard worker, Daniel said. He has two pleas. One is for the killer and the other is for any witnesses.
"Turn yourself in. It's the right thing to do," he said. "This person cannot be out there free-roaming the streets and killing innocent people. Somebody had to have seen something. Please come forward."
Anyone with information is urged to contact the HPD Homicide Division at 713-308-3600 or contact Crime Stoppers anonymously at 713-222-TIPS.
Friends have set up a GoFundMe to raise money for the victim's funeral.
For more on this story, follow Jessica Willey on Facebook, X and Instagram.