Car trembling when reaching a certain speed


When I start accelerating it starts off smoothly, but once I hit a certain speed the car starts to tremble, like it would if it was driving on a bumpy road.

I recently upgraded from unity 4.6 to 5.0 (I will never upgrade midway through a project again) and had to fix all the wheel collider values.

But what could be causing this trembling when reaching a certain speed?


Try to increase the stiffness of the sideways friction. Also, make sure that the torque is being applied symmetrically (ie. Right rear must work with left rear wheel, front right must work with front left wheel).