Don't know

It doesn't look like it, but I've heard others having the same problems with brakes too

I'm not very hard on my brakes
I'd heard it's possible to polish/glaze the surface by being too gentle with them

Don't know what's caused the corrosion though

At least I now know why my handbrake isn't as good as it once was

 

JSBear - Thanks, I've heard both good and bad about the Mintex

I've heard they're meant to be low dust, and they're so cheap I'm happy to throw them away the following day if they're no good

 

Anybody know the cause and/or solution to the rear discs corroding so badly on the inner faces?

The thickness makes them vitrually new, but the corrosion isn't good!

 

Local parts supplier has 30% off until Friday

Can somone help me out and tell me what to do?

I know I'll need new front pads, but what about the rest?

My front discs are half worn
My rear pads have loads left on them
My rear disc thickness is almost new - but the inner faces are seriously corroded

I'm tempted to buy new everything because of the 30% sale
But, these brakes are almost five years old and are far from their minimum thicknesses

Am I ok to mix and Match stuff?
Based on my current usage it'll take me 10 years to go through a set of discs, so if I miss this sale I'm sure there'll be another one by the time I need some discs

Need some help guys, what should I do?

 

I use stock pads on the street. I have no useful experience with other brands to relate.

There is a lot of corrosion almost everywhere at the rear: rotors, spring, retaining pin, pads. I recall that you said your car sits outside. I've heard that it rains occasionally in England. That could account for some. How about snow? Road salt could do that, and you don't need a lot of exposure.

The corrosion on the back side of the rotors suggests that you might have a sticking caliper, as Pumalex said. It's so rusted because the pad isn't making much contact with the disc. Can you press the pistons back into the cylinders easily? If not, you might want to do a caliper rebuild. OTOH, rear brakes don't work as hard as the fronts, as you can see. Perhaps you just need to do some hard stops occasionally. That would skim off the rust.

Your other surfaces look normal to me. The wear limit on the rear rotors is 26 mm. You are well above that, but you're probably reading a bit high because of the rust.

What I would do is replace the front pads, and then go out and do some hard stops from rather high speeds as part of the bedding procedure, and see if it cleans up the inner surfaces of the rotors. If not, I'd do a caliper rebuild. BTW - if you are not changing the rear pads, then you should get the same compound for the front. Otherwise, change all 4.

Jon

 

It has been kn to snow over here, but only when it's not raining

 

Thanks Jon

Both of the rear discs have rust on their inner faces, I'm therefore guessing (perhaps wrongly) that it's not a fault with the calipers seizing

Think I'll try some hard stops Luke you suggested to see if that has any impact

I tend to drive my car very smoothly most of the time and doubt the brakes even get warm so I might be being too delicate with them?

I'm in two minds at the minute
One one hand I'm thinkng I should just replace everything as its reletively cheap to do so,
But on the other hand I'm thinking it's taken almost five years to get that little wear out of the discs, and that replacing them all is just OTT

I'll do some hard stops tonight and see what that does
100-30mph sound right?

 

the handbrake doesn't have anything to do with the rust since it uses a drum style brake inside the disk, it doesn't use the regular caliper.

As FAST_FVD said, i would remove the rear brake and check the travel of the caliper, see if they actualy works correctly and clean and grease everything. If everything works right, i would do a couple of hard stop to see if the disk comes back to it's normal look. You might have some grooves that will form in the disk, if you have some, either try to get them turned (i wouldn't do that on a car that sees track but since you drive it smoothly) or change them.

I really think you should start by cleaning everything, those brakes looks like rally cars brakes, not sports car brakes

 

Gotcha, will do

I haven't got a pad spreader, can I use something else, or do I need to buy one?

I'm guessing I just.....
remove the wheel
spread the pads
Undo the two caliper bolts and remove the caliper

Nothing more to it is there?

 

you will have to mess with the little pins and spring type holder to remove the pads but yeah, that's pretty much it, very easy to do.

 

Yeah, I've read the diys

Just wanted to make certain that It's ok to remove the caliper from its mount and them press the brake pedal

Do I need a pad separator to open them back up again?

I'm guessing I'm just looking for a sign of movement - IE, I'm not trying to touch the pads together, just need to see that they're free and not seized

 

Ant -

I do it like this: Leave the caliper in place. Remove the retaining clip, then press out or use a drift pin to bang out the spring retainer pin and the spring. (Actually, there is a very cool little tool for that from TraqJunk)

Afterwards, take a small piece of rubber and put it on the caliper side, then use a pair of channel lock pliers with one jaw on the ear of the pad and the other on the rubber piece and squeeze until the pad is clear, then slide it out. You can then reach in and press the pistons back with your fingers, or place the rubber pad on the rotor and pry them back in. They should move relatively easily. Note that there are pistons on both sides, so one side being clean and the other rusty could mean that some of the pistons aren't moving freely.

The seals are lubricated by brake fluid, so you can sometimes free them up just by running them in and out a couple of times. Put a thin piece of metal or a worn brake pad in the gap and pump the brake to run the pistons out. If you don't put anything into the gap, it might be very hard to get the piston to get back if it goes all the way out to the rotor. Then pry them back. Repeat a couple of times. Replace the pads and go.

I usually do several stops from 80-40 or so. There is a good description on the Pagid web site.

GL,

Jon

 

Jon = Hero Status

Thanks mate, seriously appreciated

I'll have a go at the weekend and report back with my findings

In the meantime I'll most likely buy pads & discs for the front & rear, as the 30% sale ends on Friday

 

don't push on the brake pedals when the caliper is out, you will pop out the pistons. As Jon said, just try to see if they will move into the caliper (inward) with the prying method. If you can do that, then press the pedal and if they go back thight on the disk, you are ok. Once the caliper is out, you should be able to push them back in the caliper with your hands. If they are way too stuck and won't get in with the channel lock method, then they are seized.

 

Thanks mate
Rep points have been sent to both you and Jon