USC is investigating McKnight's use of the vehicle to find out if it is in violation NCAA rules. It is against NCAA rules for athletes to accept benefits from agents or marketing representatives, or to accept "extra benefits" based on their ability.
The Times reported McKnight has been seen driving the SUV, which the California Department of Motor Vehicles says is registered to Scott Schenter.
Schenter, 47, works in marketing and owns a company that registered a Web site called 4joemcknight.com, according to the newspaper.
Schenter's wife, Dawn, told the Times he was in South Africa. Reached by e-mail, Schenter didn't respond to a list of questions sent by the newspaper, according to the report.
If McKnight is in violation of NCAA rules, it could affect his eligibility. USC plays Boston College in the Emerald Bowl on Dec. 26 in San Francisco.
USC is already being investigated by the NCAA and Pac-10 regarding accusations that running back Reggie Bush and basketball star O.J. Mayo received improper benefits during their time at the school.
McKnight is the Trojans' leading rusher with 1,014 yards this season.
"Compliance has this in a full review and so we'll have to wait and see what happens with that," coach Pete Carroll said. "I really can't tell you anything. I don't know anything more than that."
McKnight told the Times on Wednesday he has ridden in the Land Rover but never driven it. McKnight's girlfriend, Johana Michelle Beltran, works as a secretary for Schenter, he said.
"I know I can't drive cars I'm not supposed to," McKnight said. "If somebody said they spotted me driving, they're seeing wrong. I don't even have the keys."
McKnight and Beltran are the parents of a 10-month-old son, Jaiden. McKnight told the Times the Land Rover belonged to "my baby mama's boss."
"I never talk to her about it," he said of the SUV. "I just see it whenever my girlfriend's around with my kid. I ask no questions. I just do what I got to do."
Information from The Associated Press was used in this report.