Quality of Pattern Parts

Surely acoustic wear indicators are nothing to do with the quality of the pad material?

Many manufacturers are dropping wear indicators for both sides. The pad with the indicator goes on the nearside of the vehicle as that has been shown to wear the fastest. You may find that even genuine pads only have one indicator now.

Well I suppose it could be argued that you do. (Assuming you are the owner/driver, and are specifying or fitting non-OEM parts that you believe may be inferior.)

Chris

What 'law' is there regarding the wear indicators in the UK?

I was not aware of that. I suppose the idea of any asymmetry when it comes to brakes just feels wrong.

Mind, I remember when wear indicators were rare, and the only way of detection was the metal to metal grinding sound, or an advisory at the MOT.

Hence my question. Some makes of replacement pads do have 2 wear indicators.

I was wondering if there was any element of policing? If its trading standards I'll give up now!

The law is couched in terms of matching or exceeding OEM quality.

I would have said "quality" would include having wear indicators if this was specified by the manufacturer.

YMMV

Why would you expect a pattern part to match or exceed OEM? I would not, in fact I would expect that its quality would be less than OEM. I repeat the question: What 'law' is there regarding the wear indicators in the UK?

That _was_ the audible wear indicator :-)

Or, with disc brakes, 15 seconds to check the amount of material left and done on a regular basis.

It takes longer than 15 seconds to jack up a car, remove wheels and inspect.

Yes I know you can sometimes see by other means like looking through the wheel, but that's not true for many cars.

"spare parts of matching quality" means exclusively spare parts made by any undertaking which can certify at any moment that the parts in question match the quality of the components which are or were used for the assembly of the motor vehicles in question.

Therefore if Mitsubishi specified wear indicators at the time of manufacture, then spare parts made available for general consumption ought to match the specification aka quality.

If you feel that doesn't answer your question, what are you trying to say?

There are other documents to be searched for on the 'net that say similar things. There ought to be some UK legislation somewhere that reflects this directive.

[...]

It's a legal responsibility for the driver of a car to make certain it is safe before (s)he drives it, In respect of brake pads, this would normally be done by ensuring the vehicle was serviced to manufacturers schedules. (I've never known a vehicle that would wear out a set of pads between services, although I had one that came close on my youth!)

Audible pad wear indicators are unreliable. Some drivers would not be aware what the noise was, some would play music too loudly to hear the sound, and others may have limited hearing.

Single wire sensors were introduced. These have a wire buried in the pad, and when that makes contact with the disc, completes a circuit to earth that illuminates a warning lamp. This system is ineffective as it's not fail- safe. A broken wire would stop the warning.

Current systems are two wire. These use a loop of fragile wire buried in the pad. When this contacts the disc, it breaks, opening a circuit which the electronics detect as a fault. It's reasonably fail-safe as a broken wire (very common!) will show as a fault condition.

[...]

As I previously stated, the likelihood is that pads with one sensor per set are actually nearer to the OEM standard than those with two.

Again as my previous post, it is the end-users' responsibility to ensure suitable parts are used, whether that is an independent garage, or an owner doing their own maintenance.

It wouldn't be the responsibility of Trading Standards to check things in case they were faulty; their role is to enforce standards once a breach has been detected.

Chris

and that document is about parts in France.

No-one is saying that spare parts manufactures don't need to make parts that meet the spec available.

they are saying that there is no law that says you have to fit two disks with warnings on the car.

you are at liberty to fit a normal part on the other wheel, so presumably part manufactures can supply such.

tim

2 small points:

a. you were quoting text from EC (as was) regulations. Regulations - unlike Directives - apply direct. They do not need UK legislation to give effect to them.

b. those regulations have expired and been replaced by EU 461/2010. They don't define the terms but the supplementary guidelines (2010/C

138/05) have:

"(20) In order to be considered as ?matching quality?, parts must be of a sufficiently high quality that their use does not endanger the reputation of the authorised network in question. As with any other selection standard, the motor vehicle manufacturer may bring evidence that a given spare part does not meet this requirement."

I always find it refreshing to remind myself how Brussels strives to make the law clear and accessible!

Been like that for a long time. My '97 BMW had only one indicator per axle, and pretty certain my earlier one was the same. And I've never seen any vehicle with one indictor per pad.

EU requirements that brake parts meet 85% of OEM spec is only for braking function. They don't test them for design features or when worn out.

As all pads on an axle should wear at an equal rate one pad wear indicator is sufficient. If the pads don't wear at an equal rate it's rarely the fault of the pad maker but your maintenance or fitting.

Is is possible to fit the wear indicator pad on the outside, pulled by the sliding claw? As this can jam resulting in reduced pad wear with higher wear on the moving pad, the wear indicator should be on the pad that is pushed by the piston - the inner pad.

Many thanks for all the replies and appreciate the responses.

I was unaware that it was acceptable for a single wear indicator per axle, although original equipment was 1 each side.

Thanks again.

[...]

I first came across this 'one indicator or two' on a Mk7 Transit; these changed from two to one indicators during early production. I was told Ford had researched it, and found that the nearside always wore first.

That might be borne out by the fact that all Mk7's have the wiring both sides, with a blanking plug in the unused one, presumably to limit the differences between LH and RH drive vehicles.

That would only apply to sliding calliper designs of course.

However, if a sliding calliper drags, it is equally likely that the pad on the non-piston side would wear most because it would tend to stick on.

Chris

It is usually the opposite - the piston side will continue to wear whilst t he non-piston side doesn't get involved. Indeed, the piston side will likel y see increased wear than normal given it is doing all the work.

Even if the non-piston pad were to seize solid in contact with the disc it will wear only to the point where there is insufficient contact to continue to cause further wear. If there's the slightest chance of movement in the caliper the disc will tend to still knock it back (or cause sufficient wear to equate to the previous condition).