South Jordan has both a Frontrunner stop and two Trax Red Line stops. The Frontrunner runs North and South parallels I15 throughout the Salt Lake Valley.
The SoJo station is hard to miss from the free way on the boundary between South Jordan and Sandy. Meanwhile the Trax stop is on the other side of South Jordan in Daybreak. In fact, the Red line begins (or ends) in Daybreak.
Full Frontrunner, Trax and Bus schedules for South Jordan are available here.