I'm about to change my break pads, and I notice my left rotor isn't as smooth as my right one, it has some grooves towards the top of the rotor, does it have to be completely smooth? Or should I be fine just replacing the brake pads?
My car has 133000 miles.
My car has a manual transmission.
If your rotors do not have a good clean smooth surface for the new pads to ride on then the pads will not be able to seat properly. This can lead to vehicle pull to one side or lack of braking force and increased stopping distance. I would recommend replacing or resurfacing the rotors.