Table 1 shows three common service brakes related problems of the 2012 Chevrolet Express.
| Problem Category | Number of Problems |
|---|---|
| Brake Master Cylinder problems | |
| Brake Hoses, Lines/piping, And Fittings problems | |
| Service Brakes problems |
I manage a fleet of 53 school buses, model years ranging from 2008 to 2015. I have noticed a trend with the hydro boosters and master cylinders, they tend to leak internally on these gm vehicles some have begun to leak as early as 30,000 miles. I expect to have to replace all of these components, on every bus in the near future. As the fleet ages the trend is getting increasingly worse. I believe this is a dangerous situation because I am vigilant with keeping up on this issue, however I am not sure that the general public will have the same understanding about the danger of this design flaw. I have had buses come in bleeding brake fluid or hydraulic fluid.
Parking brake cable found rubbing on the hydraulic service brake line, forward of the rear axle on drivers side of chassis. Wear is evident on hydraulic service brake line and parking cable, along with component parking brake assembly was stuck under.
Violent shaking while applying brakes.