2nd Service Expensive and New Brake Discs needed? Really?

[Lovemyev]

@N2STY has it absolutely nailed !.
Single acting piston, swinging calliper(s) on the rear, if I remember correctly ?.
The inner brake pad comes into contact with inner face of the disc ( rotor ) first, then the calliper upper body is pulled inboard and then outer fiction pad, then comes into contact with the outer face of the brake disc.
Therefore the inner friction pad applies pressure to the disc, slightly before outer friction pad comes into play.
This affect can be clearly seen in the pictures you have kindly provided.
The outer face of the disc has become very pitted by rust and it's decline has been quickly accelerated by a simple lack of use.
If the calliper slide mechanism is slightly sticking / seized then some binding and dragging of the pad is very common and some pad squeal can sometimes can be heard when first moving off from a rest.
Of course, these friction pads are never assembled into the callipers bodies with any anti seize lubricant at the factory.
I am willing to bet that the fiction pads will still have a fair bit of fiction material left on them, but they will be discarded if / when the new discs ( rotors ) are installed of course.
At @N2STY has been very proactive I think and checked for third party suppliers for the rear discs and pads and sounds like that the rears are not yet available.
I believe the ZS EV was the first ZS to get the electronic handbrake, prior to this I think it was a mechanical handbrake.
This MAYBE the reason why the brake disc's and pads are not YET available via third party suppliers.
This leaves a visit to the main dealer unfortunately.

 

[Edoc16]

I agree @Alb.
The problem here with MOT testing is this, if the cars fails due to what the TESTER considers is a failure issue ( rust / pitting on brake disc's etc ) then we either agree to replace them, or we are not receiving a pass ticket !.
What we consider is a pass matters not unfortunately, we are not testing the car.
This can be very frustrating for somebody who held a MOT licence, but is over ruled by somebody else.
Some issues can end up being what I describe as a "Opinion" snag.
One tester will pass it, while the next one will fail it !.
I NEVER use a main dealer for MOT testing, ever.
Some main dealers offer then for "Free" - But I have come to learn that nothing comes for free in this world.

"nothing comes for free in this world"....not wrong

 

[Alb]

It may prove cost effective to do a strip, clean and grease every year or bi-yearly at most.

 

[N2STY]

It may prove cost effective to do a strip, clean and grease every year or bi-yearly at most.

Definitely but it should really be done under a service
When I was a Apprentice for Ford we was taught to do this as part of a service and remove brake drums to clean out and adjust the self adjusters

 

[Lovemyev]

@ChrisT .
PURELY for entertainment value only, I will post a link to video below, that features how the FRONT pads and disc's are replaced on a ZS ICE ( It's not an EV but it will be very similar process ).
Sorry it is not in english, but a picture replaces a thousand words I guess.
At least you get an idea of the work content that is involved in the process.
This should only be carried out by suitably trained people of course !.
Enjoy !.
@N2STY - Interesting to note it is single acting piston callipers on the front of this car, not what I expected to see to be honest, I though it would be twin pots for sure ?.
Could be twin pots on the EV ???.

 

[N2STY]

Only good sports cars have pistons on both sides more often then not and motorbikes plenty of cars have twin pistons but still on the same side probably a lot cheaper

 

[Lovemyev]

It may prove cost effective to do a strip, clean and grease every year or bi-yearly at most.

James of "James and Kate" fame on Youtube, is a brilliant, honest and very knowledgeable mobile EV tech.
He spend a lot of time driving between jobs in his MG 5 work horse and loves it !.
The back is all kitted out with all of the necessary gear.
He covers LOT'S of miles travelling and servicing / repairing all kinds of EV's.
Almost every older EV's he services, he end's up having to carry out a full brake service, which means a full strip / clean and lub of the brakes or even a disc and pad replacement, usually caused by corrosion and seized handbrake mechanisms.
Older Tesla model S are noted for this at the rears, Nissan Leaf's also.
Brake services on EV's are where its at folks !.
If ONLY I was a bit fitter and bit younger.
.

 

[Bodgerx]

There's probably some decent thinking around the iD3 having drum brakes on the rear. Probably some argument to completely do without rear brakes at all on an EV with a rear motor.

 

[N2STY]

BTW if someone is going to do this them selfs please don't use copper grease like the old days I use mainly 2 greases on brakes for the back of pads and contact areas I use ceratec its owned by tmd friction so brambo, Pagid, mintex and so may more brands don't matter which brand as long it says ceratec normally £3 a tube this can be used for the pins but I prefer a good silicone grease for pins
But this kit is just as good on amazon

​

 

[N2STY]

There's probably some decent thinking around the iD3 having drum brakes on the rear. Probably some argument to completely do without rear brakes at all on an EV with a rear motor.

Drums are just as bad if not worse plus you can't see what's going on with out removing them

 

[Delboy102000]

I have to agree with that @N2STY.
The rears get even less work to do than the front and they are not over worked either .
Rear handbrake callipers / motors etc tend to stick or seize and the disc's are prone to pit with rust.
All mainly due to the lack of any serious work to conduct really.
The braking fiction pad material tends to me much thinner on the rears than the front pads from new as standard and I understand why, less wear !
This is reflective of the fact that about 75% of the braking efficiency is done by the front brakes.
When the callipers are assembled with the pads when new, they never receive any type of anti seize lub, which just makes matter even worse.
Road smuts / salt / water spray and lack of any service travel / use, results in an early target for a brake service or even rear disc and pad replacement prematurely in my opinion.
MOT's are a prime target.
I guess it's a different set of circumstances between ICE and EV vehicles.
Disc's on a ICE tend to get replaced when they either become worn below the min thickness recommend by the manufacture, or more often than not, because the disc's have warped due to excessive heat ( causing disc run out ) and this can be felt through the steering wheel as a vibration when braking.
With EV's it is almost the opposite situation, the disc's will getting replaced due to the lack of use, not over use thats for sure !.
Unless you have a high performance Tesla etc and you drive it like you stole it .
Regardless, you going to get caught for replacements either way !.
Hoping that they will be third party firms suppling disc's and pads by the time I need any for my car, because if they are OEM parts ONLY, it usually means it's time to remember to put a board down the back of your pants when you visit the dealer !.

One thing I have experienced on my Trophy LR since I took del in February has been when reversing off my drive on a slight downhill slope, I sometimes get a really loud squeal. This never happens going forward, and yes my car is always on max regen so I mostly only use brakes for final stop. When I do first service around the year end I will ask for a report. Incidentally I have taken out a five year service plan with mots included. About £750 in monthly instalments.

 

[Lovemyev]

BTW if someone is going to do this them selfs please don't use copper grease like the old days I use mainly 2 greases on brakes for the back of pads and contact areas I use ceratec its owned by tmd friction so brambo, Pagid, mintex and so may more brands don't matter which brand as long it says ceratec normally £3 a tube this can be used for the pins but I prefer a good silicone grease for pins
But this kit is just as good on amazon View attachment 11693View attachment 11694

​

I agree - the new brake lub's they are using today, are a much better "fit for purpose".
For this reason alone, copper grease can be seen as the "Old School" now.
But copper grease is better than no grease at all, I guess.
In the USA they use a silver anti seize grease on brake parts, but you can not apply it without any protective gloves because it is extremely hard to remove from your skin.

 

[N2STY]

But copper grease is better than no grease at all, I guess.

I do disagree to this unfortunately like most greases Copper grease reacts with rubber and swells it can make the pin grab to the swollen rubber also is not sensorsafe even though copper is not magnetic copper can make the magnetic sensors react funny

 

[N2STY]

One thing I find funny about brakes is the snobbery over brands like don't use padgid or mintex but love brembo so I normally show them this

Oh look SAIC too

 

[Lovemyev]

One thing I have experienced on my Trophy LR since I took del in February has been when reversing off my drive on a slight downhill slope, I sometimes get a really loud squeal.

I have witnessed the same thing on a couple of occasions in our Trophy LR purchased in March 2022.
It is only likely to be surface rust that has built up on the discs overnight or over a couple of days of standing still.
You back off the drive and the pads produce a squeal from the surface rust.
I have witnessed a bit of brake squeal from the front when reversing my car on a couple of occasions, am I concerned, not in the least to be honest.
Not because I wish to disregard it, but as a X Tech myself I do have an understand what is going on and what is the likely cause.
If I removed the pads / cleaned and lub'd them correctly, then it would probably go away.
Had the pads been installed in the callipers with some appropriate brake lub, then its very likely that this would never happen in the first place.
Strangely though, our Gen 1 ZS EV never did this at all in two years and 20,000 miles of ownership.
Here is another interesting fact, when the handbrake motor stripped out on that car and it was recovered to the local dealer.
They decided to replace both the handbrake actuator motor and the whole rear brake calliper assembly, which was a belt and braces approach and the correct thing to do !.
When the parts arrived ( 4 weeks latter ) they quickly set too in installing the pads etc.
They correctly lubricated all of the mating surfaces with brake lub ( copper grease as it happens in this case ) which assembling with brake lub was the correct process to follow in my mind.
I ask myself this question, had it been assembled with the correct brake lub in the first place, would it ever had failed ?.
Because some thing had caused it to fail prematurely ( like water causing it to seize maybe ).
We will never know I guess ?.
I mean come on, who ever installs pads without using some type of the correct brake lubrication ?.
It's a problem waiting to happen IMO.
Oh ......... know I get it, this is where your brake service cost comes into play.
I am wiling to make a bet that a standard service or service plan does NOT cover a FULL clean / strip and lub brake job.
Brake pad wear itself is normal done on a visual inspection check only.
Removing the pads etc is likely to be a customer chargeable option for sure.
Very unlikely to be covered under warranty unless there is a linked serious problem with the braking system.
You would be surprised to know what is NOT covered under a standard service cost / plan.
Just to name a couple, brake lining wear is not covered, if you need new pads, you are paying.
On a ICE model, clutch lining is not covered ( unless contaminated by an oil leak, that is covered under warranty ) which is a huge expensive job.
Exhaust pipe ( ICE ) - not covered under a standard service plan.
Air con service - NO.
Brake fluid replacement - customer chargeable or it is included and the price is reflective.
With VAG models, it is an additional £80 on top of the price of your service, HVAC service is the same, every two years.
The list goes on.

 

[Lovemyev]

I do disagree to this unfortunately like most greases Copper grease reacts with rubber and swells it can make the pin grab to the swollen rubber also is not sensorsafe even though copper is not magnetic copper can make the magnetic sensors react funny

I do see your point very clearly, but I a little bit puzzled why copper grease would be applied to any area, that would come in direct contact with any of the rubber parts like the slide pin gators etc.
Which I totally agree, is not recommended !.
The slide pins should be coated with a thin film of suitable anti seize lub like you recommend.
Even a red rubber grease that is formulated to be in close contact with rubber is fine.
Copper grease is suited ( if you wish to use it ) when it is in direct metal to metal contact points, between brake shoes and the backing plates etc, very little movement, but it prevents a squeal when the footbrake / handbrake is applied etc.
Times have moved on and better produces are available on the market now.
I just wish that cars where assembled using these products, instead of totally disregarding them.
But then they would not be able to charge for a brake service every two years I guess !.
You know how that works !.

 

[N2STY]

May be I am being a bit unfair to copper grease but like you say thing have moved on pretty much all cars Now use speed sensors/abs sensors if to much copper filings end up near the sensors it can end up expensive especially now technicians will just get a fault code and replace a part when is the theory of wipe down and clean maybe we'll it needs also a lot of people used copper slip on pins that pass through rubber and slap it all over the back of pads the piston is metal on metal but remember every piston will have rubber orings when they swell your piston will no longer retract freely anyway all I am saying there are better suited products out there now and some cost less
Edit : like this there all the same

 

[Edoc16]

James of "James and Kate" fame on Youtube, is a brilliant, honest and very knowledgeable mobile EV tech.
He spend a lot of time driving between jobs in his MG 5 work horse and loves it !.
The back is all kitted out with all of the necessary gear.
He covers LOT'S of miles travelling and servicing / repairing all kinds of EV's.
Almost every older EV's he services, he end's up having to carry out a full brake service, which means a full strip / clean and lub of the brakes or even a disc and pad replacement, usually caused by corrosion and seized handbrake mechanisms.
Older Tesla model S are noted for this at the rears, Nissan Leaf's also.
Brake services on EV's are where its at folks !.
If ONLY I was a bit fitter and bit younger.
.

Don't we all :-(

 

[Cocijo]

Switch regen to lowest setting and give the brakes a good workout. Not crazy until they glow like an F1 car - but reasonably heavy breaking frequently applied over a journey. I would not change those discs personally especially on a lease car. I’ve seen far worse.

 

[RobinH]

Switch regen to lowest setting and give the brakes a good workout. Not crazy until they glow like an F1 car - but reasonably heavy breaking frequently applied over a journey. I would not change those discs personally especially on a lease car. I’ve seen far worse.

^ this.
Good advice for anyone with an EV to do once a week or so.
The most expensive service item I ever had on my Volt was the rear discs which had massively corroded through lack of use.