Certain vehicles will exhibit a brake dragging or locking up condition once warmed up after master cylinder replacement. This is most likely due to the pedal mechanism or booster pushrod keeping the master cylinder slightly applied, impeding the capability of the master cylinder to allow expanding fluid back into the reservoir as the fluid warms up.
To check for this condition, duplicate the dragging condition, raise the car and loosen the fasteners holding the master cylinder to the booster. If the brakes release, the condition has been verified.
In some vehicles, where equipped, it is necessary to adjust the master cylinder pushrod in the booster to accommodate for manufacturing tolerances in master cylinders.
Other possible causes:
• Improper brake light switch or pedal stop adjustment holding the pedal down slightly.
• Aftermarket devices attached incorrectly under the dash interfering with pedal returning to pedal stop.
Courtesy of Centric Parts
