Usually, this train runs on time. Sometimes it is early into Albequereque and into Los Angeles because of padding in the schedule.
I don't remember the exact lenght of this layover. But if it is less than 2 hours, you are flirting with a missed connection.
Also, you can track the trains progress on the Amtrak website. The train arriving into Los Angeles is train 3. If you play with the dates and departure points along the route, you can track a train's prgress from Chicago to LA.