Brake discs and pads

[Yugguy1970]

I wonder if they would try to weasel out of say a caliper piston failure if they knew you'd had the brakes done elsewhere.  Brakes are one of the things that even now, with less time and inclination, I do like to do myself as they are relatively easy and satisfying to do.

[loz8]

Expecting to see a mention of RELAX in showroom,didn't see any, but

outside used cars had mention of warranty of unused period of the years remaining,out of 10.

I .suppose servicing would be mentioned to buyers. Not a bad selling tool.

[loz8]

Back to brakes,I was expecting pitting on discs getting a mention,tho all looked bright and shiny,but

the front inner surface were very rusty and out of sight. Hope this isn't the norm.

[TonyHSD]

2 hours ago, loz8 said:

Back to brakes,I was expecting pitting on discs getting a mention,tho all looked bright and shiny,but

the front inner surface were very rusty and out of sight. Hope this isn't the norm.

That’s normal on these cars. Once in a while you can do some long slow downs with moderate force in neutral N, helps clean the brake surfaces of the discs and pads and dry out moisture of slider pins boots, extends maintenance periods and keep braking system works correctly. 👍

[loz8]

As Flash22 said,the upsell.charge for brake fluid [recently changed fluid] have you ever needed a top up after new discs and pads?not me.

also a charge for a job I asked not to be done.The bill was so big I've only just noticed.

so they can stuff joining service scheme,where nothing is itemised and you dont know what has been done.

[loz8]

What I did'nt mention, 8mm on one pad,half that on the other,thats shoddy service to me.

Reason fo rusty inside disc,we dont remove wheels on every other service,so its hard to see it. Must think I've just got off the boat.

Why do they employ idiots?.

[Mooly]

On 7/12/2021 at 6:03 PM, loz8 said:

As Flash22 said,the upsell.charge for brake fluid [recently changed fluid] have you ever needed a top up after new discs and pads?not me.

2018 would  be the last time I used Toyota for a service and they persuaded me to have the rear discs skimmed. I was sceptical at the time because the only reason was to remove a lip of rust but they argued that doing this now would meant the discs would last as long again... 

2019 I switched to an independent and they commented that the brake fluid was quite and that they had checked for leaks and found none. I suspect it was the pads initially wearing more due to the now visibly rougher surface on the disc and so the fluid dropped. No such problems the following years  although the rear pads were replaced this year (same independent) as they had seemingly worn pretty quickly. I think they wore because of the rougher disc surface from skimming them.    

[Guest]

15 hours ago, loz8 said:

Why do they employ idiots?.

I wouldn't say idiots but parts changers, at the customers' expense, until the problem hopefully goes away. Blindly following what some diagnostics on a computer tell them. All without proper old school diagnoses, observation and skill!

That's why I take my 1962 classic car to a proper older mechanic for it's M.O.T. (yes, I know it's exempt).

Uneven pad wear could indicate a lack of lubrication/maintenance of the caliper slide pins, hence rust on one side of the disc.

[loz8]

not serviced,we all know it,but customer service [short for idiot] talk tripe. I'm loosing confidence,for instance expensive plug change at 60k,but only 30k of use,  maybe less,                        would they change them? Question it,"its all in the service price"quote.

[AisinW]

When I change the front brake pads with new pads and rotor, I need to remove some brake fluid in the reservoir, almost overfill. Toyota dealers keep topping it off every time they do oil change.  Even after 3 years no brake fluid flush, it is still less than 1% water and almost like new.  I am not sure why Toyota Europe has 2 years brake fluid flush in the maintenance book.  In USA, we do not have brake fluid flush in schedule maintenance but Toyota recommends brake fluid flush after pads and rotors replacement that normally after 100 000 miles.  The Iridium Denso  also have 60 000 miles in Europe but 120 000 miles in USA for the exact same engine and spark plugs. 

[Tomfromfife]

Hi, I have a 2019 RAV4 which lived in Scotland until February 2021 when we moved to Wiltshire.

Because the car wasn’t used a great deal because of Covid so only covered 7800 miles and there is some rust on the surface of the discs. The last service in June reported that the pads were all like new and some surface rust on the discs. It will be due for an MOT in June 2022 so is it likely that it could fail the MOT due to the surface rust? No amount of braking removes the rust.

This is the problem with regenerative braking I guess. Toyota would know this so should fit better discs that don’t rust. What type of discs could be fitted that don’t rust, like stainless steel ?

[Stivino]

All metals will show signs of oxidation.  It won’t be rust and it’s use, it should clear up in time.

I wouldn’t even consider replacing the discs.

 

 

[TonyHSD]

2 hours ago, Tomfromfife said:

Hi, I have a 2019 RAV4 which lived in Scotland until February 2021 when we moved to Wiltshire.

Because the car wasn’t used a great deal because of Covid so only covered 7800 miles and there is some rust on the surface of the discs. The last service in June reported that the pads were all like new and some surface rust on the discs. It will be due for an MOT in June 2022 so is it likely that it could fail the MOT due to the surface rust? No amount of braking removes the rust.

This is the problem with regenerative braking I guess. Toyota would know this so should fit better discs that don’t rust. What type of discs could be fitted that don’t rust, like stainless steel ?

It may just need the callipers to be taken off the support brackets, cleaned and lubricated the slider pins, this is what get stack and prevent the outer pads moving and cleaning the disc surfaces, can happen on one year old car too. If you do clean these every two years and replace brake fluid the brake system may not need any parts replacement for over 10 years or more than 100k miles. 👍

[Gerg]

Particularly with regards to an Auris hybrid, but probably others too, I found it much easier to remove the brake calliper carrier (2 x 14mm bolts) when cleaning up the rear callipers on our car.  The amount of rust and crud on that part meant cleaning it on the car was nigh-on impossible for the inside pad seat.

On some other brands of cars (VAG etc.), that carrier is a complete pain to remove as the mounting bolts end up so very tight, so best avoided until a disk replacement is needed on those.  But this didn't seem the case with the two Aurises I've done.  Also removing the carrier allows you to tape up the slider-pin/ caliper threads and wire-brush the pad mounting faces in a water-filled container, which massively reduces the amount of dust produced.  (The container will look disgusting afterwards, though.) The above mentioned carrier bolts are torqued to 37Nm iirc.  I used a hot air gun to dry off all the bits that were still damp, so as not to trap any moisture.

I ended up (delicately) using a hand file to remove the corrosion underneath the stainless steel pad bearing plates; the rust was that bad.  Shame that a dab of some brake lubricant or other wasn't put on here when the car was being made, it could have saved a lot of work later.  It's got some on there now.

The above suggestion was meant for occasional d-i-y ers (like me!), rather than the trade-experienced amongst here, who probably have their own preferred ways of doing this job.

I was surprised how long it took to get the rear brakes sorted when I was trying to be thorough with cleaning them, I don't know how a service garage can do this without racking up a sizeable bill, maybe they have some short-cuts that I don't know of !?

[AisinW]

The rear Bosch brake parts are OK in mine. There are some wear about 0.5mm on the disc and 30% wear on the pads but nothing to worry about.  In Auris II, the brake caliper pins are 2x13mm bolts, not 14 mm like other Toyota.  Removing the whole caliper assembly, 17mm bolts are easy with a breaker bar.  I always use silicon grease for all brake components because they are very sticky and safe for rubber parts.   The rear brakes on Auris I sometimes has issue with jammed slider pins.  Cleaning and re-lube it with silicon grease every 50 000 miles is not a bad idea.  

I do not flush brake fluids in hybrid before 10 years.  They last very long and does not have problem with water adsorption as much and the anti corrosion additives are also not degrading too much.  https://techno-fandom.org/~hobbit/cars/maint100k/   Over 10 years, the brake fluids are still in 90% life. But I know some Prius 3rd gen has issue with the rear brake slider pin too. 

Don't fix if it does not break, Toyota way.   Many scheduled maintenance in Toyota Europe manual are actually overdone (brake fluid, spark plugs) and forgot to emphasise more important maintenance: Oil change every 5000 miles/6 months for short trip/city drive/Taxi/Uber, etc,  ATF-fluid change every 60-90k miles, and clean throttle body+MAF every 100 000 miles.  

[AisinW]

6 hours ago, Tomfromfife said:

Hi, I have a 2019 RAV4 which lived in Scotland until February 2021 when we moved to Wiltshire.

Because the car wasn’t used a great deal because of Covid so only covered 7800 miles and there is some rust on the surface of the discs. The last service in June reported that the pads were all like new and some surface rust on the discs. It will be due for an MOT in June 2022 so is it likely that it could fail the MOT due to the surface rust? No amount of braking removes the rust.

This is the problem with regenerative braking I guess. Toyota would know this so should fit better discs that don’t rust. What type of discs could be fitted that don’t rust, like stainless steel ?

Surface rust is normal in brake disc. Stainless steel is soft and cannot be used as brake disc, we need high carbide steel (carbon) like on the railroad.  The only thing that you may need to watch is uneven wear on the brake disc like what I had in my front disc from corrosion creep up under the surface on the outer lips.  I still pass with the brake disc like that in Germany TÜV  bi-yearly inspection.  They said everything is perfect and normal.  For MOT, go to a special shop that only do MOT, not common mechanics who repairs cars. They will have conflict of interest by pressing you to change this and that. Or dealership if you still have the warranty and Relax warranty (cover brake disc but not pads).  

I replace the brake disc/OEM Advics not because of corrosion that does not cause any issue. The problem is the PULSATION from the Uneven stripes on the RADIAL pattern (lines like through the diameter of the disc).  You see bluish colors about 20 lines there.   When my brake disc is hot from driving in Alps or Blackforest area, it starts pulsating.  It runs fine for 1 or 3 hard braking but not on the long downhill braking.  I mitigate the problem by putting to B mode.  I replace it just because it is cheap, total of less than €100 with Aisin pads and Zn-coated Zimmermann disc.  No more corrosion and pulsation.  

[Cyker]

I think you can get stainless steel brake discs for bikes, but they don't use them on cars because stainless steel is more brittle than cast iron and where iron will warp, a stainless steel brake disc would likely crack. It's also a much harder material and has less friction with normal car pads, unless you use e.g. metallic pads.

Some manufacturers like EBC coat their discs so they don't rust, except where the brake pad scrubs away the coating, but just using the brakes will be enough to clean that part so it won't be an issue unless you hardly ever drive!

The brakefaces on my Mk1 and Mk2 were always super shiny. The rest (Hub and edges especially) were rustier than a... very rusty thing. Haven't looked that the ones on the Mk4, but expecting them to have a lot more of a 'patina', since 90% of my braking seems via regen!!