Brake

[outnumbered]

Took the car out this afternoon and noticed a constant vibration when applying the brakes hard. I guess the best way to explain it is that it feels like a tire with a flat spot. The car has 23,000 miles. Is it likely the pads needs to be replaced? I don't track the car, but I am hard on the brakes from time to time.

If they need to be replaced, should I go back with stock pads?

[ViperGeorge]

Sounds like what many would call "warped rotors". Typically a result of uneven deposits of pad material on the rotors. Check how much pad is left. If the pads still look good you can try to correct the problem by bedding the brakes. Find a lonely road, accelerate to 60 then brake hard to 10, immediately accelerate to 60 again and repeat hard braking to 10. Do this 10 times then drive for about 15-20 minutes with minimal use of brakes. If you are using racing pads then after this cool down repeat braking process from 100. If this doesn't fix your problem you will have to "turn" your rotors or replace them. Turning them uses a lathe to resurface the rotor face.

[nuviper]

Have a look at your rotors to see whether there's glazing sign on it. If so, then you can check you pads and follow what ViperGeorge said. Good luck.

[outnumbered]

Thanks. I contacted my Viper Tech last night and he said my pads are fine; mentioned "rotor pulsation". I will try what you suggest and see what happens.