As I stated in another thread, my soft pedal was resolved with bleeding the rear brakes. I didn't break it down to which side since I did them both then checked. I am thinking that the air is getting in the caliper past the seal when temps get cold sitting in the garage all winter. The fluid is cold, contracting, the seal is cold and contracted, allowing air to be sucked in past the seal. It won't leak fluid because when pressure is applied, it reseals it self. Just an idea because I have nothing else.
Originally Posted by
GraphiteGhost
Decided to see what I could do with the soft brake pedal I had, and finally fixed it! I and a friend did a complete brake bleed starting right rear, left rear, right front then left front. The old brake fluid was dirty AND it had some kind of black silt in it. Once I flushed new fluid into the calipers, I took another 3 or so ounces of clean fluid out. After doing each caliper, I tested the feel of the pedal. That's when I found out the first caliper (right rear) fluid change resulted in a full firm pedal. When the job was complete (including a rotation side to side of the tires) I took it for a test drive and it was 100% firm and solid. Put about 200 miles on her coming back home from Hickory NC, with no leaks and super firm brake pedal.
Used CARQUEST DOT 4 brake fluid, it was on sale for 3 bucks a 32oz bottle. Best 3 bucks spent in a while!
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