2004 GMC C1500 pedal will go to floor

2004 GMC C1500
47,888 MILES • V8 • 2WD • AUTOMATIC
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SJIEERERFA
  • MEMBER
  • 1 POST
bleed all four wheels- no broken pads or shoes-no fluid leak- brake pedal usually is ok but always feels soft - can the vacuum change during low rpms or slow speeds
Feb 21, 2010 at 3:50 AM
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MHPAUTOS
  • ✓ASE Certified Mechanic
  • 31,937 POSTS
  • ASE Certified Mechanic
Hi there,

This may be a by-passing master cylinder, this is when the fluid by-passes the primary cup seal in the master cylinder with out leaking externally, this will give you a soft sinking pedal that will pump up hard again.

Mark (mhpautos)
Feb 21, 2010 at 4:15 AM
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