Feel warped; I don't know if they are, I think probably not. The cyclical increasing and decreasing of brake effectiveness that you get with warped discs is only there at low speed. There is no rapid cycling at high speed. The problem was intermittent too.I believe warping was mentioned in the initial post?
Agreed, this is a Pagid disc that has done 80K miles and used two sets of Pagid pads. It is just the A2 that plays me up.Thats even more confusing as most pagid discs have a coating that seem to protect the non contact area of the discs really well and are indeed good quality, i dont know why you have been having so much trouble!
I fitted Bosch discs in January as the discs the car came with were quite tarnished and tatty making the brake pedal feel a touch "soft" on initial application, will update if they do the same as i have standard 15" wheels also.
A product that is fantastic for all things rubber is rubber grease, its red and i use it on tons of stuff for example slide pins on brake calipers
Feel warped; I don't know if they are, I think probably not. The cyclical increasing and decreasing of brake effectiveness that you get with warped discs is only there at low speed. There is no rapid cycling at high speed. The problem was intermittent too.
A bit of a mystery as to the cause.
Agreed, this is a Pagid disc that has done 80K miles and used two sets of Pagid pads. It is just the A2 that plays me up.
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And still looks servicable!!
Never come accross soft and hard disc/pad set up other than all pads since absestos was abolished seem to wear the discs
Yours look more like they have been dorment for a year or so and suffered in the weather, one of my rear galaxy ones did the same during lockdown as off road but looks ok now
I don't have a DTI; I was playing with the idea that this A2 problem justifies one. If I had one I would have the runout figures by now. Also needed for adjusting wheel bearings on Mercs.You're an engineer Phil: got a DTI with a mag stand? Be interesting to see the run-out. Only thing you do have to be careful of is to use some pipe / sleeves to allow the disc to be held by all five wheel bolts during measuring.
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My front discs are only lasting 10K miles tops. They develop a hard ring around the outer and inner edges that wears away the edges of the pads then discolored rings start to develop and the brakes feel warped when coming to a stop. I've just today fit the third set in as many years, gone for ATE this time, usually fit Pagid.
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The disc mess:
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Pads with plenty of life if they would wear evenly. Badly messed up piston. Disc retaining screws made of cheese, had to be drill then heated to cherry red to get one of them out.
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Thoughts? Could this be a defective caliper? Both sides have this problem
Thank you.
When you have a full set of caliper notes, they are good, why not copy them to the How-To section.Looking again: do you live in an aggressive environment? I don't mean 'whattta you looking at, do you wanna take it outside mate?' so much as being near the coast / waterfalls / muddy lanes etc?
It's just that the inside of the 'hub' looks remarkably rusty to me for a young disc, plus those screws usually come out O.K.. The other thing is looking at the slider rubbers, the piston and the rust on the sliding portion of the pad edges, it's hard to think that the pads were being fully released as per my above post.
I forgot to add another element to my caliper notes above, so will do that now ...
Also needed for adjusting wheel bearings on Mercs.
Ah, well I think the latent engineering gene in us would say you couldn't draw any conclusions about the quality of the pads / discs until the rest of the system was perfectly healthy. I'd tentatively suggest case closed?@Rusty911 I don't mind at all, E Class front wheel bearings have a run out specification. I did them by feel.
If I had to put a few quid on the root cause of my problem I would gamble on it being these pistons sticking. One is really bad around around the main seal and was weeping fluid. That one was really stuck and took some pressure of compressed air to blow it out. Both of them have uneven rust build up on the piston to pad back plate surface. I don’t suppose this would be a problem until the pad anti squeal coating wore through. May explain why I don't have problems for 6 months? Once the pistons are contacting the metal of the pad back plate applying the brakes will attempt to twist the pistons in the bores causing metal to metal friction. Only slight but that may be just enough to leave just too little drag.
The new pistons now blow out very easily, had to blow them a little further out to fit the dust shields correctly.
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All indeed relavant but from what a can see of those discs there is no evidence of binding, quiet the opposite????
To be honest I have never had brake problems before in 40 years of motoring, 12 cars, all up 1 million miles (two of us contributed), all cars DIY maintained. I started the thread to learn about brake problems because I really don't know. What do you think the cause is?