Rear Discs Surface is rough...9000miles

[fbitz777]

Ok as I was having the tires rotated I had the service guy look at the rear discs as they felt very rough to the touch.

Anyhow the guy told me the brake pads are fine and it looks more like the rear brakes have not been used in a long time
and the discs might be "rusted".

As I am now trying to use the rear brakes via the handbrake or breaking in reverse downhill I can hear some kind of grinding noise. Also the handbrake does not really slow the car down as quickly as I would expect.

Any way to clean the discs off? if the pads are still up to spec how can the discs be so rough looking? It's been a rough winter with lots of salt and dirt.

 

[jmueller065]

I don't think the handbrake activates the rear discs. I thought the handbrake was a rudimentary drum brake inside the center of the rear brakes. (As the handbrake is cable actuated and the rear discs are hydraulically activated).

Just slam on the brakes really hard for a stop...get as low of a brake score as possible (especially getting off the freeway). Make sure no one is following you when you do this of course. You probably don't have to hit them very hard. I've noticed that when its really damp out the discs are a lot more grabby and hence its really easy to tell when they engage.

 

[sefs]

Just put the car in neutral while braking. It will be all friction braking.

 

[hybridbear]

Just put the car in neutral while braking. It will be all friction braking.

Exactly. This is better than slamming on the brakes. Braking while in Neutral (or with a full battery before regen is available) means you're using all friction brakes.

fbitz - do you regularly experience no regen when you first start driving on a full charge? The braking during this scenario hopefully will keep the discs/rotors clean.

 

[fbitz777]

I never paid too much attention to the no Regen after battery is filled, most of my trips start flat or uphill.

As a side note Regen is NOT active in Reverse?

 

[WattsUp]

As a side note Regen is NOT active in Reverse?

No.

And, even if it was, it wouldn't do much good. How much reverse braking at speed do you do?

 

[WattsUp]

Just put the car in neutral while braking. It will be all friction braking.

Exactly. This is better than slamming on the brakes.

Shifting to neutral while at speed is not the safest thing to do. You should always have power while driving.

In any case, you don't need to do this (slam on the brakes) just to give the brake pads/rotors a work-out. Just brake a little harder than normal such that the Brake Coach gives a score well under 100% -- perhaps 60-70% or so. A score like that means that the friction brakes significantly contributed to slowing the car.

I don't try particularly hard to brake heavily... I don't really think about it, to be honest. I just drive normally (for an FFE) but I know that, sometimes, my braking isn't "perfect" (according to the Brake Coach). My rotors are nice and shiny.

 

[EVA]

The rotors on our ICE Focus look awful also.

If using the brakes doesn't work - you'll need to have them surfaced at a shop. By not working, I mean you notice the car doesn't stop normally when you apply the brakes with a low brake coach score (or they pull to one side). If the car stops in a straight line and the brakes work - don't worry about what the rotors look like.