87 subaru gl wagon front brakes
3 Answers
No you do not need to open anything to push back the piston in a caliper. And yes you need a tool to do this on yours, the pistons screw back in, they do not just push back in. You'll see the design in the face of the piston for the tool. Otherwise if the piston is hollowed out like normal, then you can use the "C" clamp.
Go to Oreilly auto parts or similar store and get the proper tool, around $10 plus or minus. I doubt the fronts are the issue, it is usually the rear brakes that are also used as the parking brake.