[sensible]

Originally Posted by johnung

It's not unusual to need new pads at that mileage but BMW rotors wear slowly. I've measured 30k mile rotors with 80% of their wear material remaining. Truth is that without actual caliper measurements of pads and rotors, any anecdotal stories or any recommendations that are given are meaningless. Mechanics/ dealers recommend rotor and brake pad replacement all the time without any data proving that it's really needed.

335i blue M-Sport Brake 370mm rotors come 30mm thick and 345mm rear rotors come 24mm thick. Both have 1.6mm of wear material. See photo for wide mouth caliper for measuring. Probably cheap from AliExpress.

Don't let anyone put non-BMW parts on without you approving the brand & the part number. There's a lot of junk parts out there and "this is the brand that we always use" isn't good enough.

I'd trust Zimmermann rotors which are well made. Suggest Zimmermann front (370mm) drilled part# 150.2911.52 and Zimmermann rear (345mm) plain. Drilled provide better bite and shed water better for safety in the rain. Mercedes, Porsche, McLaren, etc. use drilled on their street cars for this reason.

US-made Hawk 5.0 pads are the best street pads that I've found. I've seen them on AmazonUK so perhaps other UK suppliers have them too. See photo for part numbers. I'm assuming your M-Sport blue brakes are Front370mm/Rear 345mm.

Hope this helps!

Obviously, these pictured above are one piece discs that are the same material as the disc at the hub. These will rust and be visible through most BMW wheels. If you want those similar to what BMW fit with an aluminium hub you will need to buy the two piece disc with the alloy centre.

My dad had a 66 plate Audi Q3 with one piece discs. Last week it went into a garage to have the hubs painted for the second time as they looked so bad and rusty.

Something to consider when making your purchase.

[NISFAN]

Originally Posted by Sullym6

So nothing to be worried about then, guess the driver must have been driving it hard. I had 47k out of mine previously so was a little concerned

Probably more city mileage than motorway where you can go long stretches with no brake application at all.

Brakes on these cars are exceptional. Don't forget they are heavy cars and as fast as a super car from the 80's.

[Wills2]

Originally Posted by sspade

No word of a lie...

I am on factory brakes all around and approaching 91k miles :

Very believable I got 90k out of my discs and pads on an M3, some people are very binary with their brakes and don't coast/slow down prior to a stop light or corner etc...and just slam on at the last minute.

[isleaiw1]

Originally Posted by Wills2

Very believable I got 90k out of my discs and pads on an M3, some people are very binary with their brakes and don't coast/slow down prior to a stop light or corner etc...and just slam on at the last minute.

Whereas my daughters (now My) Mini needed new front discs and pads at 19k miles...

And now is saying it needs new rear pads at 21k!

[johnung]

Originally Posted by sensible

Obviously, these pictured above are one piece discs that are the same material as the disc at the hub. These will rust and be visible through most BMW wheels. If you want those similar to what BMW fit with an aluminium hub you will need to buy the two piece disc with the alloy centre.

My dad had a 66 plate Audi Q3 with one piece discs. Last week it went into a garage to have the hubs painted for the second time as they looked so bad and rusty.

Something to consider when making your purchase.

Good point! Zimmermann, unlike BMW, zinc-coats their rotors against rust so they should hold up better.

I don't have a part number for a Zimmermann 2-piece aluminum hat drilled rotor. StopTech makes some very nice aluminum hat (black) drilled rotors that are typically more expensive than Zimmermann.

StopTech Front Cross-Drilled 370x30
128.34144L, 128.34144R

StopTech Rear Cross-Drilled 345x24
(for most common 185mm emergency brake)
128.34147L,128.34147R
See photo.

I got fed up with how bad my Original BMW rotor hats looked. I scrubbed of the rust and grime with a fine wire brush and Formula409 household cleaner. Then sprayed it all down with brake cleaner. I painted the sides of my rotor hats with G2USA Caliper Paint in Silver. It's a two-part epoxy like paint that brushes on and levels out as it dries to a sprayed-on finish. Easily applied right on the car. A pack of 36 silver handled brushes is sold by Harbor Freight for $3. Only 1 brush comes with G2 Kit.

There is a whole group of standard colors and more expensive custom colors. I did my calipers in G2 Black and rotor hat sides in G2 Silver. Still look brand new more than a year later. See photo.

https://www.g2usa.com/

G2 has a working time of a couple hours once it's mixed so put car up on stands to do all four at once or buy two kits for two at a time. Also must apply within specified ambient air temperature range. As temp rises above that the G2 stops flowing and starts to gunk up the brush. Can be had for <$50 at TireRack in US. G2USA will ship internationally. Contact directly.

[johnung]

Originally Posted by johnung

Good point! Zimmermann, unlike BMW, zinc-coats their rotors against rust so they should hold up better.

I don't have a part number for a Zimmermann 2-piece aluminum hat drilled rotor. StopTech makes some very nice aluminum hat (black) drilled rotors that are typically more expensive than Zimmermann.

StopTech Front Cross-Drilled 370x30
128.34144L, 128.34144R

StopTech Rear Cross-Drilled 345x24
(for most common 185mm emergency brake)
128.34147L,128.34147R
See photo.

I got fed up with how bad my Original BMW rotor hats looked. I scrubbed of the rust and grime with a fine wire brush and Formula409 household cleaner. Then sprayed it all down with brake cleaner. I painted the sides of my rotor hats with G2USA Caliper Paint in Silver. It's a two-part epoxy like paint that brushes on and levels out as it dries to a sprayed-on finish. Easily applied right on the car. A pack of 36 silver handled brushes is sold by Harbor Freight for $3. Only 1 brush comes with G2 Kit.

There is a whole group of standard colors and more expensive custom colors. I did my calipers in G2 Black and rotor hat sides in G2 Silver. Still look brand new more than a year later. See photo.

https://www.g2usa.com/

G2 has a working time of a couple hours once it's mixed so put car up on stands to do all four at once or buy two kits for two at a time. Also must apply within specified ambient air temperature range. As temp rises above that the G2 stops flowing and starts to gunk up the brush. Can be had for <$50 at TireRack in US. G2USA will ship internationally. Contact directly.

Photo of StopTech rear 345x24 cross-drilled

[johnung]

Originally Posted by johnung

Photo of StopTech rear 345x24 cross-drilled

Photo of G2USA Caliper Paint in black on caliper and in Silver on sides of rotor hat. Look like new over a year later.

[HighlandPete]

Originally Posted by Sullym6

Thanks for all the responses, I don't have much choice on parts they use unfortunately but the car is priced well. The positive is that they are doing what needs to be done to get the car sorted according to the AA report
Going to see it mid week so hopefully I will be back in a bmw soon

When you say you don't have much choice, do you mean they'll simply fit the cheapest discs that they can source, or will they fit the cheaper OE equivalent (two piece discs) like Brembo or TRW. Something like Brembo or TRW quality will be fine.

I'd insist on OE quality, (don't have to be BMW), or I'd walk.

[Goneinsixtyseconds]

Originally Posted by Wills2

Very believable I got 90k out of my discs and pads on an M3, some people are very binary with their brakes and don't coast/slow down prior to a stop light or corner etc...and just slam on at the last minute.

My 440i went at 54,000 still on original pads with plenty of life left in them. It was even still on the original front tyres as well.

[Sullym6]

Originally Posted by HighlandPete

When you say you don't have much choice, do you mean they'll simply fit the cheapest discs that they can source, or will they fit the cheaper OE equivalent (two piece discs) like Brembo or TRW. Something like Brembo or TRW quality will be fine.

I'd insist on OE quality, (don't have to be BMW), or I'd walk.

Not bought the car yet going on wed hopefully. I spoke to them on the phone and they told me what the AA report said so they are getting it sorted. I can't demand they fit certain parts until I actually commit to buy. If they haven't done by wed and the rest of car is ok I will prob just ask for some money off and get the disks and pads replaced myself

[Sullym6]

Going to see the car tomorrow so what are the common issues I should check

Looking on the forum it seems to be
Steering rack noise
squishing sound when going over speed bumps
Hesitation from around 1500rpm is egr

Thanks
Sully

[KRS_SN]

335d. front brake pads done at 22000 and then at 50000 miles. i can definitely tell an improvement in baking after i change though. I changed them when there was still life in the pad much like tyres for performance i change them before they reach their legal limit.