When do you change the timing belt on a 2007 chevy cobalt ? thanks in advance?

i have a 2007 chevy cobalt with almost 60000 miles and i'd like to know when to change the timing belt %26amp; water pump assembly. thanks in advance.When do you change the timing belt on a 2007 chevy cobalt ? thanks in advance?you dont have a belt its two chains that go from the cams to the crank(and a couple more sprockets ... as for water pump im surprised it hasnt gone out yet...look at the block see if you can see any orange tint by the pump(gonna need a flash light) if its orange around it might as well replace the pump to since you have to remove it to replace the gasket,your already up in mileage might as well...When do you change the timing belt on a 2007 chevy cobalt ? thanks in advance?All the maintenance intervals for your specific vehicle\year\drivetrain combination can be found in your owners manual.When do you change the timing belt on a 2007 chevy cobalt ? thanks in advance?change it at 100k along with the water pump