My 2007 Malibu has mushy brakes first thing in the morning and very hard brakes in the afternoon, are they safe? My mechanic says he can’t find a problem.
mushy brakes is often a sign that there are air bubbles in the brake fluid. When the brakes are used several times while driving, the bubbles tend to get broken up into very small bubbles, and this allows the fluid to behave more like straight fluid, thus the brakes firm up. I would recommend you have the brake lines bled, and the fluid replaced with new fluid. There may also be a leak in the master cylinder that allows the air in in the first place. The other common contaminant in brake fluid is water, which bleeding and replacing the fluid will eliminate.