Both rear brakes don't work. Front work fine. When I pumped the brakes to see it maintains a firm pressure. It builds up then slowly depress almost to the floor
I think you have air in the lines and you will need to bleed them...
Here is a video....https://www.google.com/url? sa=t&source=web&rct=j&url=http://m.youtube.c om/watch%3Fv%3Dn1NvtUwfRJc&ved=0CCQQt wIwA2oVChMIlZ_Yvq3wxwIVQnI- Ch3w9wtZ&usg=AFQjCNETqCrlyBjqekQIuo4Lw cMRxFdJGA
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