Is your car still under warranty? I would think you still have many miles left.
Anyway, it's quite possible you have more than one issue.
A "Low grinding and rattling sound" when you apply the brakes is either excessively worn brake pads or loose/missing retainer springs.
The "womp, womp, womp" that you hear while driving could be a warped rotor, which can occur if your pads were excessively worn and overheated the rotors.
Also a common noise for vehicles with alloy rims that have "Center caps" is the tension spring sometimes comes loose/falls out on the inside. This will make an intermittent rattle while driving.
Finally, whatever your issue turns out to be, you never want to keep driving a vehicle when there's a suspected brake problem.
You're taking unnecessary risk with your life as well as others!
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Monday, March 15th, 2010 AT 10:44 PM