jordhandson
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I couldnt find the 350 disc but i found a pic of another disc this is the same setup i used when grinding the fly wheels on trhe milling machine, works for me
- Thread starter Mr Fro
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Mr Fro
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Cheers @jordhandson, that's what I would end up doing if I don't stump up for new ones.
Interesting what you say @Johnnybravo - the F10/F11 are renowned for tramlining. I had the rear tyres replaced with Michelin pilot sport 4s a few months back. They made no difference to the tramlining. I'm waiting for the fronts to wear a bit more before I do them too.
Interesting what you say @Johnnybravo - the F10/F11 are renowned for tramlining. I had the rear tyres replaced with Michelin pilot sport 4s a few months back. They made no difference to the tramlining. I'm waiting for the fronts to wear a bit more before I do them too.
good mechanic I trust will only fit original / main dealer disks on anything quick or anything heavy, had too many warp
I warped 2 sets of pagid disks on the front of my XJR before I talked to him... pagig are supposed to be decent and I very rarely pushed the car hard - and even when I did it was nothing like the car is built for etc.
can't remember what the main dealer disks set me back... I really like that car so didn't really care
I warped 2 sets of pagid disks on the front of my XJR before I talked to him... pagig are supposed to be decent and I very rarely pushed the car hard - and even when I did it was nothing like the car is built for etc.
can't remember what the main dealer disks set me back... I really like that car so didn't really care
Ubique
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Came across this today:-
Very new brake pads (11mm) on very old brake discs, done by an independent who told the driver that the minimum thickness was just a scare tactic used by dealers....
The minimum thickness is stamped into the hub of the disc.
These were well below - typically there is 2mm of wear on new brake discs, roughly two sets of brake pads worth of wear.
Now, What you want to do with your own brake discs is one thing, and if it goes wrong then you have to bear the cost and possibly account for your actions, to not change or strongly recommend changing the brake discs if they are below discard thickness or within 0.7mm (Merc. wear limit for replacing pads only) of it is just plain wrong. The vehicle was in for an unrelated issue (autostop not functional due to reduced starter battery capacity) and the issue with the discs was picked up on a visual inspection, replacement front brake discs & pads was £310, cheaper than the diag & replacement battery!
Very new brake pads (11mm) on very old brake discs, done by an independent who told the driver that the minimum thickness was just a scare tactic used by dealers....
The minimum thickness is stamped into the hub of the disc.
These were well below - typically there is 2mm of wear on new brake discs, roughly two sets of brake pads worth of wear.
Now, What you want to do with your own brake discs is one thing, and if it goes wrong then you have to bear the cost and possibly account for your actions, to not change or strongly recommend changing the brake discs if they are below discard thickness or within 0.7mm (Merc. wear limit for replacing pads only) of it is just plain wrong. The vehicle was in for an unrelated issue (autostop not functional due to reduced starter battery capacity) and the issue with the discs was picked up on a visual inspection, replacement front brake discs & pads was £310, cheaper than the diag & replacement battery!
Lewis_RX8
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Thought you dodgy car mechanics charge for brakes when they don't need to be done not the other way round
Morrisman
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The average set of discs and pads for an average car is chump change. The manufacturers don't stand to make any profit from it, so I'm not sure why this is being played as some sort of a scam.
Thinner discs means less heat dissipation, easier to overheat, lose brake efficiency etc. Plus, you have to draw the line somewhere, every part that wears down needs a tolerance. How far out can the piston push before the seal clears the bore it sits in?
Thinner discs means less heat dissipation, easier to overheat, lose brake efficiency etc. Plus, you have to draw the line somewhere, every part that wears down needs a tolerance. How far out can the piston push before the seal clears the bore it sits in?
Ubique
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The pistons can go until the pads are metal-to-metal, it's actually the other way round - the pad wear sensors will be cut prematurely by heavily lipped discs, meaning that the dash warning will come on at 4mm friction material remaining, rather than the 2mm they're designed to trigger at. Most manufacturers recommend minimum friction material thickness of 1.5mm for heat dissipation.
Ubique
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It's because of those 'historical practices' that visual health checks recorded on video and emailed to the driver were brought in, difficult to argue with measurements done in front of you, some still do though.... usually the ones that just manage to get into a <insert car badge of envy here> without thinking of how they'll keep it on the road.Thought you dodgy car mechanics charge for brakes when they don't need to be done not the other way round
That really depends on the car. I bought a set for a Mondeo mk2 once, £15 each... They were (genuine) Brembos. Even now they're only £17.10ea (although it doesn't give you the choice between Brake Engineering, BREM TECH or Brembo).
PhillipM
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The wear sensors are usually attached to the pads so they wouldn't be any different with them coming on, and metal-to-metal would be different distance depending on the disc thickness. If you're getting down to 4mm+ thinner than a new disc when it's metal to metal you can definately have the pistons pop out - I've seen it happen!
AVI_8
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Apologies if this has been mentioned before as I haven’t read all of the comments but juddering brakes are often caused not by warped disks but by friction material from the pad getting deposited on the disks.
I had this once on my 911 after a track day.
It‘s caused by coming to a stop when the disks are extremely warm whereby the area of the brake disk against the pads gets friction material transfer, it can be visually noticeable as a dark patch on the disk.
I had this once on my 911 after a track day.
It‘s caused by coming to a stop when the disks are extremely warm whereby the area of the brake disk against the pads gets friction material transfer, it can be visually noticeable as a dark patch on the disk.
Ubique
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They do come on earlier due to the lip on the disc cutting into the wear sensor rather than them being worn through on the working face of the disc.
Well I've stripped a fair few brake calipers down and the piston has to be extended maybe 2/3-3/4 the width of the yoke before it'll come out, maybe some specific combination of pads, discs & calipers will do as you suggest, I've never seen it happen on production vehicle brakes though.
Ubique
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Also overheated discs becoming polished & hardened on the working face can cause brake judder, agree about the friction material deposits though, quite common.
Edward Teach
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Brake pad wear sensors,
I need a newer car and van
I need a newer car and van
Probably better rather than newer...Brake pad wear sensors,
I need a newer car and van
Although some makes fit pad wear "squealers", small tabs of metal that are meant to contact the disc when the pads are worn low and make a horrible squeal. Not in my experience that they work consistently however so I wouldn't want to rely on them.
Ubique
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Not seen those for years! I've a feeling they are used on some of the older PSA and Ford stuff - I remember going out to a 'breakdown' where the blokes brakes were metal-to-metal on his front discs and he was moaning that it 'just happened, no warning', I said to him that someone had cut the squealers off the brake pads, his response was along the lines of 'oh yer, that was me - didn't want them damaging the brake discs.....'
