Quote:
Originally Posted by Simmy
the disc on pic no3 is pitted at the top thats not surface rust. dont take risks with brakes just change them your life is worth more than that.
|
What's the problem with pitting? Are drilled discs dangerous? In the old days it was common for motorcycle racers to leave a set of discs out in the garden after thoroughly degreasing them then spraying them with salty water to get the maximum amount of rusting and pitting to aid wet weather performance.
Now we have sophisticated multi-channal electronics looking after the car's dynamics, I suspect you could fit different pads, discs and tyres to each corner and nobody would notice the difference - the car would still pull up straight as a die under emergency braking conditions. I'm not suggesting anyone do this but my point is pitted discs are not an issue since the risk of pirouetting down the road from unbalanced brakes has practically disappeared. Cracked discs - fair enough. Pitting? Who cares other than misinformed MOT testers?
If an MOT station fails you for pitted discs ask them to point out under what rule they are failing you on as pitting is not necessarily "significantly or obviously worn". As long as a car passes the brake test in terms of power and balance and there's no physical cracks, breaks or leaks anywhere, there's sufficient disc and pad material - the car should pass. Obviously they can fail it on ABS warning lights, corroded brake pipes, insufficient fluid etc. Getting drivers to replace perfectly serviceable pitted discs is one of the biggest motoring scams out there.
Incidentally, if you find yourself in a deserted car park, reversing hard then applying the brakes hard is a good way of cleaning up the rear discs - the weight transfer to the rear will put some brake load on the rear - particularly where load sensing valves are fitted. Obviously only contemplate this where you are 100% absolutely alone and there's nothing/no-one to hit!