Review on 🔄 Dorman M630439 Brake Master Cylinder - New and Improved for Enhanced Performance by Marcel Robinson

Only installed for a month but works perfectly. One important tip: If you're installing on an Impala, you'll probably need to take it somewhere to complete the system upgrade. After we bled and installed it, we were unable to completely bleed the air from the system. I asked the local GM shop to complete the upgrade and they even had a hard time doing it. GM even issued a TSB (Technical Service Bulletin) with a special bleeding procedure because they had so many problems where they couldn't get all the air out of the system. This requires a scanner capable of activating the ABS solenoids.