On my car the front left caliper sometimes sticks. Mainly when it is warm out, and in heavy stop and go traffic, ( I live in Houston,Tx,so this is every day). I have replaced the caliper twice, the rotor, and pads several times. I have called a dealer, they would not tell anything,except " you will have to bring it in and let us take a look" routine. The hose on that side looks a little worn but does not leak. Any suggestions ?