Well, it's Friday night, time to play mechanic. Thought I would check out the rear brakes calipers this time. Seem like they might be hanging up. (Notice when at a full stop, when brake release and accelerating, there was a feeling like a rear caliper was hanging, very slight jerk) Anway, Noticed the top floating pin (Guide Bolt) has flats along the pin every 120 degrees running longitudinally. Is this normal? Both sides have them.