Did a front brake service on my Cobalt this weekend. Just a warning to everyone, the caliper slider bolts on these cars seem to be made from the same weaksauce pig iron that the strut mount stud/nuts are. The torque spec is 25 footpounds and I snapped one with only moderate hand force on a ratchet. Fortunately I stopped immediately when I felt it give and was able to back it out before it broke completely in two. These tiny bolts are $7.64 CAD a piece from the dealer.

 

Ive never snapped one of those bolts on a Balt, in 4yrs and easily 100+ caliper install/removals. They are grade 10.9 iirc, good stuff actually.

 

The rear caliper slide pins / bolts are shoulder screws on the 08-09 SS/TC. McMaster shows them as Grade 12.9, but the thread diameter/pitch calls for about 25 ft-lb of torque.

I have not touched the front Brembos but they are fixed calipers.

It sounds like someone overtorqued your bolts in the past or they used a weaker bolt.