One of the rear discs of my 03/03 Focus has a band of permanent rust (on the outer face) approximately 7 mm wide at the edge of the disc. Is this amount acceptable? The car recently passed an MOT at a Ford dealer without comment.
(The rust is the result of the car having stood idle for a long period before I bought it. I was aware that all the discs were very rusty when I bought it but the rest have cleaned up with normal use. If I've still got the car when new rear pads are required I intend to have new rear discs fitted at the same time in any case as a precaution.)
Edited by Dynamic Dave on 21/12/2007 at 10:17
|
>>Is this amount acceptable?
As it's on the rear brakes, and these aren't exactly overworked**, I wouldn't lose any sleep over it.
** Being on a nose heavy FWD car, the rear brakes will be reduced significantly in their effect by some form of pressure reducing valve, or load sensing valve. People more cynical of Ford's marketing effort than I might question the suitability of disc brakes for the rear wheels of such a car.
In fact, if the rear brakes were doing more work, it would most likely have cleaned up. What you are seeing is the rate of corrosion is greater than the rate of wear.
Swapping the discs out when you change the pads is a reasonable idea.
Number_Cruncher
|
This is very common on lots of cars, especially FWD cars. When driven lightly loaded the rear brakes are not doing much during normal driving, so the rust becomes established. Normally is will slowly 'creep in' from the outside edge.
In the past I have cleaned these up with emery cloth and then a bit of hard braking (or drive with handbrake on for a short distance - not really ideal, but it does work).
A friendly machine shop might skim the discs for £20, but Ford discs are cheap anyway, so new ones is probably the best option.
|
|
|
