Caltrain on Monday began replacing some of its trains with larger trains capable of accommodating more passengers, in an effort to avoid overcrowding.

Four train sets that currently use five-car Gallery trains will be replaced with six-car Bombardier trains, Caltrain officials said.

The swap will allow for more passengers to board the four train sets. The four train sets were chosen for the swap because they regularly experience overcrowding, according to Caltrain officials.

The Bombardier trains contain three different passenger-seating levels, with table seating on the top level, compared to the Gallery cars, which only have two passenger levels.

The Bombardier trains, however, can carry only 72 bicycles at a time, while the Gallery trains were capable of carrying 80 bicycles.

Caltrain averages a daily ridership of about 60,000 passengers, Caltrain spokeswoman Tasha Bartholomew said.

While plans to start using electric trains are in the works for Caltrain in the future, that won't happen for roughly four or five years, according to Bartholomew.

In the meantime, Caltrain maintenance crews will service and repair the aging Gallery train cars to ensure the cars remain reliable and safe to use, Caltrain officials said.