on my wife's ford focus its a 2000 zx3 five speed and when she is driving it down the road at around 30-40 mph it seems like there is something holding the car back. almost like a brake is sticking but that can't be the problem because it does not smell. It seems like it usually happens at lower speeds or it is not noticeable at higher speeds. Like every time the wheel goes around it seems like it wants to grip and hold the car back. I'm clueless on what the problem could be???????