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Was there a leak prior to the master cylinder leaking?
Did you perform the ABS system bleed?
OK, that is great information. Lets perform a check. Using a tape measure, we need to measure the travel. with the engine off, press and release the pedal 10 times fully to use up the reserve. Then hood the tape on the top of the pedal and measure to the steering wheel. Next apply about 100# XXXXX force on the pedal and measure again. Do this 3 times and post the average distance of travel.
Just for comparison in pressure do your TB as well.
Ok sorry for such a delay....
Trailblazer Average pedal travel engine off afer ten pumps of the pedal = 2" TBSS same test 2" as well.
I preformed the same exact test with the engine running and found the Trailblazer at 5 1/2" average and tghe TBSS only 3 1/2". If I apply greater pressure to the TBSS the pedal remains and is solid the Trailblazer goes and additional 3/4" and does hit the floor.
I bled the four corners I did NOT do an abs bleed... how do you? do you have procedures for that?
Thanks for your help. :-)