If the caliper froze, which happens when the seal breaks and dirt gets on the piston, the resulting heat can get so bad that the bearing grease becomes liquid and the bearings start to wear. Just another thing the mechanic will look at.

When my caliper froze in the open position, left front, the only brake I had was the right side. The car would pull to the right and shudder under moderate braking. Severe braking from 80-0 was a nightmare! I checked the right front several times with no success, only to realize that the pads were wearing and needed to be replaced. It was then I found the left pads were almost new looking and the cylinder would not move.

While pads and rotors come in sets of 2, you only need to change one caliper at a time. But, please, change the flexible brake lines and fluid regardless. They are getting old and the rubber is starting to crack, besides they are reasonably cheap.

Klaus
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Why are Volvos so endearing? Its just a car.