Updated: December 5, 2012 7:27AM
Passengers on the Metra Union Pacific North Line can expect a crowded and somewhat-delayed morning commute downtown.
Inbound train 306, scheduled to arrive downtown at 7:17 a.m., stopped after experiencing mechanical difficulties, stacking up trains behind it.
Passengers were going need to switch trains in North Chicago to another train, the 308 originally scheduled to arrive at Ogilivie Transportation Center at 7:30 a.m.
Trains on the North Line are experiencing delays of about 30 minutes, according to Metra.