ISELIN - Riders give NJ Transit mediocre marks in a new survey of satisfaction with the state's mass transit system.

The system, which serves 428,000 riders each weekday, scored a 5.2 out of 10 in the survey. It's part of an ongoing effort by the agency to monitor rider satisfaction.

Train passengers ranked it the lowest, at 4.5, while light-rail riders were more satisfied, at 6.5 out of 10. Fares, scheduling and on-time performance were the biggest concerns.

About 67 percent say they would recommend NJ Transit to a friend or relative, and 63 percent say they use the system even though they have a car.

"We are committed to holding up the Scorecard as the standard by which we get measured by the people who use our system every day," said NJ Transit Executive Director James Weinstein in a news release yesterday.

The agency received nearly 19,000 responses to the online and field survey.

NJ Transit is the nation's largest statewide public transportation system, with 240 bus routes, three light-rail lines and 12 rail lines.