Brake disc life

[m_tillman]

So, how long should they last?

I know, how long is a piece of string?!

But, related to the life of the pads would it be reasonable to have to replace discs at the same time as the pads?

This is on a bog standard very ordinary vehicle. Frankly, I really don't care how long they last, but I do care that after 20000 miles it costs more than three times what I'm used to to have 'safe' brakes.

[TheEnd]

i'd usually expect 2-3 pad swaps between disc swaps, certainly the discs should outlast the pads by a good amount.

[joewilliams]

Mine normally last 3 sets of pads.

Is it a garage recommending that they need replacing?

[drivin_me_nuts]

Depends entirely on how you drive. The disks on my M5 lasted 110k. I would certainly expect more than 20k from a runaround

[interloper]

It appears that if you let the pads wear too thin, they start to really eat into the discs, change your pads more often (ie before they are down to 80% worn out) and save £££s in the long run.

[saaby93]

Two things
If you under use your car the discs rust so dont last as long
Since the demise of asbestos they put metal in pads so they bite better but eat the discs.
Discs used to last for ever, nowadays only 2-3 pad changes?

[m_tillman]

joewilliams said:

Mine normally last 3 sets of pads.

Is it a garage recommending that they need replacing?

3 sets of pads sounds a good ball-park number to me, though even 2 wouldn't be so awful.

I've already let the garage replace them - I don't believe they are rip-off merchants. They did say they didn't actually need replacing now, but wouldn't last another set of pads. They have a lip of about 1.5mm, BTW.

My other car, same manufacturer, totally different model, so that really has no relevance, has done about 60000 and has a lip of less than 0.5mm, I reckon.

[GTstar]

so how long do pads last then?

3 series, mixed driving roads - I'm on 33k at the min with the same set from new... was going to get them done at next service which is 36k.

I always feel you get the 'oh your brakes need replacing soon, you want us to do them now sir' chat.

[m_tillman]

20000 miles seems to be the answer. Garage wanted to change them at the last service (10000). When asked how worn they were the reply was about 66% so I was expecting to change them before 15000. At 20000 miles, having had no feedback from the front end, they look extremely worn (I was actually told I had about 1500 miles left).

The front tyres only did about 15000 miles too. This stuff lasted so much longer when I was a kid, though the car itself did tend to revert to a pile of rust rather more rapidly than they do now.

I don't abuse my cars but I'm not a granny either, though I'm currently doing IAM and initially was told to get on with it a bit more. No problem with that, though now, instead of only being overtaken by nutters or law-breakers or those who can get up to the legal limit quicker than a 1.6 at 75% throttle, hardly anyone gets past me now :-). Hate to think of what it's doing to my wallet though.

Edited by m_tillman on Friday 5th March 08:49

[GTstar]

m_tillman said:

20000 miles seems to be the answer. Garage wanted to change them at the last service (10000). When asked how worn they were the reply was about 66% so I was expecting to change them before 15000. At 20000 miles, having had no feedback from the front end, they look extremely worn (I was actually told I had about 1500 miles left).

The front tyres only did about 15000 miles too. This stuff lasted so much longer when I was a kid, though the car itself did tend to revert to a pile of rust rather more rapidly than they do now.

I don't abuse my cars but I'm not a granny either, though I'm currently doing IAM and initially was told to get on with it a bit more. No problem with that, though now, instead of only being overtaken by nutters or law-breakers or those who can get up to the legal limit quicker than a 1.6 at 75%l throttle, hardly anyone gets past me now :-). Hate to think of what it's doing to my wallet though.

hmmm maybe I should get them done soon then! I'm 13k over that - no sparks yet though lol!

[saaby93]

GTstar said:

hmmm maybe I should get them done soon then! I'm 13k over that - no sparks yet though lol!

All this stuff can be changed a week after youve bought it as it's already looking worn.
Theres often a minimum disc thickness stamped on them somewhere or in the manual, which can be measured with a micrometer/vernier/ caliper (whatever it's called) avoiding the lip.

[GTstar]

saaby93 said:

GTstar said:

hmmm maybe I should get them done soon then! I'm 13k over that - no sparks yet though lol!

All this stuff can be changed a week after youve bought it as it's already looking worn.
Theres often a minimum disc thickness stamped on them somewhere or in the manual, which can be measured with a micrometer/vernier/ caliper (whatever it's called) avoiding the lip.

but I've done 33k on the original pads - never mind the discs (which I assume will last double what I've done so far)

[saaby93]

GTstar said:

but I've done 33k on the original pads - never mind the discs (which I assume will last double what I've done so far)

You're lucky you dont have a Prius to worry about, when it's discs (and pads?) last to 100k (it uses the motor for braking)

[bazking69]

In normal use I'd expect the discs to last at least the duration of 2 sets of pads.

However, I've seen discs killed in a matter of miles by unsympathetic driving and braking, particuarly on track days.

[HellDiver]

Vauxhall factory discs usually need changed at first pad change, never more than 35-40k in my experience.

The Mondeo needed discs all round at 55k - rears were just done when I got the car with 56k on it, I did the fronts at 57k.

Of course it depends on driving style and the type of miles a car does. 100k on the motorway is likely to wear the brakes less than 30k around the town all day.

[dav123a]

Bit of a resurrection but just booked OH focus in for set of discs. Got 116k on, 70k of those are hers in that time never had pads or discs changed, im thinking discs are the originals. Pads still have loads of meat in them.