gritty feel to brakes

[snapper65]

I seem to be doing a lot of "is this normal?" posts as I get used to the various new sounds and behaviours of my new (to me) Cayman S. One thing that puzzles me is that there is a sublte "rough" sound and feel to the brakes, like fine sandpaper rubbing. I wondered if this was usual?

Driving in the wet this morning and not concentrating properly, I saw to my horror that the car in front was stationary and I not, with about 2 car lengths gap. As I started to brake I knew there was absolutely no way I was going to stop in time. I slammed on the brakes, the ABS did its thing in the rain, but I did stop with 2m to spare, Utterly amazing, So I know they work!

Ive had the car just under 6m, it came with a major service from OPC so the pads/discs should be ok - but the service did miss a few basic things (like engine oil ) so its possible other things were not checked properly

[snapper65]

sorry, should have clarified. the brakes felt gritty from day one of collection and this hasnt changed, wet or dry, and i can hear a definite soft rasping sound every time i brake, but fucntionnally they appear ok

[cslwannabe]

maybe because they are cross-drilled (ie the holes)?

I bought a Boxster S last year and took me quite a while to get used to the brakes, mainly the fact that you have to press the pedal more firmly than other cars (non Porsche) which I have owned. When you do press it firmly they do stop pretty well though, as you found out! I triggered the ABS recently when a cat decided to shed one of its lives by darting out in front of me as I was coming out of a built up area into a NSL zone - in my 330Ci I used to trigger the ABS occasionally during normal (to me) driving, whereas in the Boxster it took a real emergency stop for me to trigger the ABS.

[alcatraz236]

snapper65 said:

sorry, should have clarified. the brakes felt gritty from day one of collection and this hasnt changed, wet or dry, and i can hear a definite soft rasping sound every time i brake, but fucntionnally they appear ok

this doesnt sound right, i get a similar sound but only after the car has been sat for a few days and it clears after a light application of the brakes (to clear small amount of surface rust). If you are getting it all the time and a few high speed braking runs doesnt clear it i would take it back to opc, particularly since it has happened ever since you bought it (i presume from an opc from your post)

also, how on earth does an opc mess up an oil change?

[Trev450]

It could depend on the friction material of the pads you have fitted. Some have a fairly high metal content which would make the sort of sound you describe. Do you know what make of pads are fitted?

[doozy]

I've had this exact scenario on both of my Caymans, it is almost certain to be the inside front discs corroded. The outer side of the disc can look perfect but if you can get to see the inside of the disc or feel it i think you will find it is corroded. Quite a common problem

My most recent Cayman exhibited this noise and feel when i test drove it. The front discs/pads were changed before i took delivery and the brakes are perfect now.

[rhkumar]

Personally I would take it back to the opc for them to resolve. Can't be much fun if you're worried about the brakes at all.

[melv]

rhkumar said:

Personally I would take it back to the opc for them to resolve. Can't be much fun if you're worried about the brakes at all.

+ 1........

[gl20]

doozy said:

I've had this exact scenario on both of my Caymans, it is almost certain to be the inside front discs corroded. The outer side of the disc can look perfect but if you can get to see the inside of the disc or feel it i think you will find it is corroded. Quite a common problem

My most recent Cayman exhibited this noise and feel when i test drove it. The front discs/pads were changed before i took delivery and the brakes are perfect now.

Agreed - same problem on my first Boxster that was on an OPC forecourt for a couple of months. I was not aware of this problem and they 'cleaned them up' when I took it back in after a couple of weeks but 1.5 years later it failed its first MOT for this reason (actually, to be precise, the same OPC failed it for this reason and wouldn't listen when I complained about the situation so I took it to an independent who passed it but with a caution). If the insides are really pitted it can be hard to get rid of just by heavy braking. It may not be this but I would definitely get them to look and if they explain it is corrosion then be clear it was always like this.

Lesson learned for me... when I got my next Boxster I checked the disc insides and try to make sure I drive the car at least once a week to keep them clean

[melv]

Skim the discs?

[snapper65]

alcatraz236 said:

this doesnt sound right, i get a similar sound but only after the car has been sat for a few days and it clears after a light application of the brakes (to clear small amount of surface rust). If you are getting it all the time and a few high speed braking runs doesnt clear it i would take it back to opc, particularly since it has happened ever since you bought it (i presume from an opc from your post)

also, how on earth does an opc mess up an oil change?

thanks all. I bought the car from an OPC a long way away, and I'm not prepared to make the journey back again, as Im happy with my local Bristol OPC. When I got the car it had had to have quite a big respray because of extensive stone chipping, plus two rear tyres - which they kept going on about. I suspect they had to shell out quite a bit on this and also suspect they may have skimped on the service as a result. On collection there were puncture holes in the passenger seat (i assume from studded jeans) and the steering wheel was cockeyed, both of which to be fair they agreed to recompense Bristol for correcting. As for the oil, the low oil warning light came on after only 800miles of mainly motorway use. I topped it up and have done another 3000 miles since with no discernible drop in oil level, so I can only assume it came with a low oil level in the first place

[snapper65]

rhkumar said:

Personally I would take it back to the opc for them to resolve. Can't be much fun if you're worried about the brakes at all.

Im actually not too worried about them because as stated they have just saved both my life and, more importantly, my pride -ramming into the back of a stationary Mini would have been cringeworthy. however its just one of a number of funny squeaks and noises the car makes that Im having to get used to, and Im not familiar enough with Caymans to know if its normal or not.
(boot lid still squeaks though better following PH advice/remedial action, still getting a whirring belt noise like a gale force wind which I believe is normal, and the aircon sounds like an old tractor which I think means it needs fixing)

Edited by snapper65 on Wednesday 25th January 10:32

[cragswinter]

I'd put a fiver on the inside edges of your discs being rusty

[alcatraz236]

snapper65 said:

rhkumar said:

Personally I would take it back to the opc for them to resolve. Can't be much fun if you're worried about the brakes at all.

Im actually not too worried about them because as stated they have just saved both my life and, more importantly, my pride -ramming into the back of a stationary Mini would have been cringeworthy. however its just one of a number of funny squeaks and noises the car makes that Im having to get used to, and Im not familiar enough with Caymans to know if its normal or not.
(boot lid still squeaks though better following PH advice/remedial action, still getting a whirring belt noise like a gale force wind which I believe is normal, and the aircon sounds like an old tractor which I think means it needs fixing)

Edited by snapper65 on Wednesday 25th January 10:32

i would be persistent in taking back to opc until any faults are resolved. the opcs charge very high prices which can only ever be justified by the cars being very well prepared and also being provided with a watertight warranty. I would not be happy at all if i bought a car from an opc and it had rusty discs / low oil / cockeyed steering / dodgy air con and other niggles.

[snapper65]

alcatraz236 said:

i would be persistent in taking back to opc until any faults are resolved. the opcs charge very high prices which can only ever be justified by the cars being very well prepared and also being provided with a watertight warranty. I would not be happy at all if i bought a car from an opc and it had rusty discs / low oil / cockeyed steering / dodgy air con and other niggles.

I take your point, and in principle agree. However its a 4+ hour journey each way. which Id have to do twice or stay overnight, plus nearly a tank of petrol for each journey. Plus the hassle of a non-productive day or two spent chugging up and down the M5/M6. Its cowardly I know but its actually less hassle for me, and probably cheaper, to sort it out locally.

I know I know. I am lazy and have no spine

[alcatraz236]

snapper65 said:

alcatraz236 said:

i would be persistent in taking back to opc until any faults are resolved. the opcs charge very high prices which can only ever be justified by the cars being very well prepared and also being provided with a watertight warranty. I would not be happy at all if i bought a car from an opc and it had rusty discs / low oil / cockeyed steering / dodgy air con and other niggles.

I take your point, and in principle agree. However its a 4+ hour journey each way. which Id have to do twice or stay overnight, plus nearly a tank of petrol for each journey. Plus the hassle of a non-productive day or two spent chugging up and down the M5/M6. Its cowardly I know but its actually less hassle for me, and probably cheaper, to sort it out locally.

I know I know. I am lazy and have no spine

yes i dont mean take it back to opc you bought it from, any opc should be able to fix faults under warranty

[snapper65]

alcatraz236 said:

yes i dont mean take it back to opc you bought it from, any opc should be able to fix faults under warranty

thats an interesting one. assuming the problem is corrosion on the inner face of the brake disc (as seems to be the consensus) then I wonder if 4 months down the line a different OPC would agree that this was a warranty issue rather than a wear and tear one?

Or to take it a little further, lets say I take the car to Bristol and they say "new pads and disks sir" then I had assumed that this would not be warranty covered. I might argue the case with the supplying dealer but not a different one surely? I imagine the get-out clause would be that I couldn't prove in the intervening four months that i hadn't abused it (I haven't).

[alcatraz236]

snapper65 said:

alcatraz236 said:

yes i dont mean take it back to opc you bought it from, any opc should be able to fix faults under warranty

thats an interesting one. assuming the problem is corrosion on the inner face of the brake disc (as seems to be the consensus) then I wonder if 4 months down the line a different OPC would agree that this was a warranty issue rather than a wear and tear one?

Or to take it a little further, lets say I take the car to Bristol and they say "new pads and disks sir" then I had assumed that this would not be warranty covered. I might argue the case with the supplying dealer but not a different one surely? I imagine the get-out clause would be that I couldn't prove in the intervening four months that i hadn't abused it (I haven't).

I guess the thing that may count against you is the amount of time since you bought it. If you had highlighted to them within say the first few weeks then im sure (hope?) it would have been fine (whichever opc you took it to), i.e. they cannot expect you to have to put new discs on just after you bought it. It may well depend on your powers of persuasion and you are right in that you would probably stand a slightly better chance with the supplying dealer than a different one. On some of the other non wear and tear issues you shouldn't have this problem, e.g. perhaps with the air conditioning.