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Discussion Starter #1 (Edited)
had my i3 in for the fuel pipe safety recall and it was all done while I waited, no problems there. interestingly though a note about brake pad wear and disk corrosion. It said my pads (front) were down to 3mm and the disks were heavily corroded.

I checked the disks after some manual brake applications and I thought they came up pretty clean with no wear ridge and only slight grooving, possibly nothing to worry about there. perhaps it just looked bad with a cursory glance. The pads however a different matter, they were indeed worn down to 3mm and although the wear light has not come on yet, I would normally replace pads that looked as worn as they do. Rears looked fine and loads of pad material on them.

Interestingly I:
  • Don't allow the cruise control to brake for me down hills (I want that energy)
  • Almost never use the brake pedal (virtually all 1 pedal driving)
  • Very careful when the battery is full as I realise the car will apply the brakes, not regenerative until a few % is out of the battery.
  • Car is always kept garaged (allowed to dry outside first if wet) and is 3.5 years old
My mileage.....28,000 miles, now my wife's heavy diesel needed pads (and they weren't as worn as the i3s) and disks at around 32,000 miles. So why should I be surprised? I guess because I thought with regenerative braking ad 1 pedal driving my brakes would last a lot longer than this....something like twice as long actually. Why I think this is because on my 11 year old 80,000 mile Honda insight (2000 year), my brakes were still fine and it also had regenerative braking, but not 1 pedal driving like the i3, the regen wasn't strong enough!

In fact I think it's fair to say I have never seen so much pad wear on any car I have ever owned at 28K miles. My driving style is economy and as if I have one of these pointed at my car.


I am going to ask them for a quote to do just pads for the front and disks/pads, will post back on how much they want for the work.

Pricing including fitting (inc VAT with my discount):
  • Pads only for both front wheels (inc new wear sensors) £249
  • Pads and Disks £435.
It's 2.5 x what I would normally pay for disks and pads (after-market) to be fitted at a fitting centre and 60% more than main dealer prices for other makes of car. Probably normal for BMWs though.
 

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Very interesting.

I too took my car in for the fuel pipe safety recall this week, and they also carried out the BMW Vehicle Health Check, which was stapled to the back of the invoice. No mention of anything of concern was pointed out to me, but on getting home I noticed on the Vehicle Health Check form said,

"Brakes

Front Pads 8mm. Approximately 42% worn
Rear Pads 10mm. Less than 10% worn"

I drive a 94Ah REX January 2017 registered with only 1964 miles.

My driving style is also 1 pedal driving and usually in EcoPro+.

Any thoughts anyone?
 

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Discussion Starter #3
Very interesting.

I too took my car in for the fuel pipe safety recall this week, and they also carried out the BMW Vehicle Health Check, which was stapled to the back of the invoice. No mention of anything of concern was pointed out to me, but on getting home I noticed on the Vehicle Health Check form said,

"Brakes

Front Pads 8mm. Approximately 42% worn
Rear Pads 10mm. Less than 10% worn"

I drive a 94Ah REX January 2017 registered with only 1964 miles.

My driving style is also 1 pedal driving and usually in EcoPro+.

Any thoughts anyone?
I do have some thought as to why this may be happening and if I'm right. I think it's something BMW should code into the car to correct. I am also going to take a guess that your car is not garaged almost all the time, as mine is and stays out in the rain etc..? This is because yours have worn very quickly

I think that the discs corrode up, which they do remarkable rapidly and more so when you drive carefully. This in turn puts massive wear on what are softish pads on the relatively infrequent times they are used e.g. cruise control with automatic braking when going downhill, ESC EBD etc.. all the various stability controls. in addition they will apply when the battery is cold and also on the odd occasion you misjudge. So perversely I think the 1 pedal system actually encourages this massive wear.

The rears don't get used much at all apart from in stability control and then only rarely and will carry a smaller % of the braking, so they don't wear so fast. My rears are fine and will probably need replacement at around 50+K miles.

I think BMW need to code the car to apply the brakes periodically to clean them up and not let high levels of corrosion build up and if possible after brakes are dry a/and or rain has stopped quick 100 yards up the road and application of brakes before garaging......sadly I used to try and remember to do this....but often forgot.

P.S. I think they quoted me ex VAT prices...making it an already very expensive job, even more so. This is because I was quoted £320 for a simple pad replacement at another BMWi dealership.....which quite frankly is unbelievable.

I have found an independent who will do it and although not as expensive, are still NOT cheap.
 

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Thanks for your comments, but I just want to confirm that my car is garaged, and the discs are always dried off after washing the car. I have checked today, the front discs are smooth with a mirror finish - so there's no corrosion there. I'm horrified at the prices you've been quoted as both of us have owned cars since the 70s, which have never needed pads to be replaced so, this has come as quite a shock. Remember I haven't done 2000 miles yet! Incidentally my previous car was also a BMW i3 REX (60Ah) and it had exactly the same use etc. and after 12000 miles in two and a half years, pad wear was not even reported.

We pull a caravan with a BMW 430d and after 30,000 miles the front brake pads are showing no signs of wear.

So why do the i3s have such a serious brake pad problem?

Can anyone with an i3 indicate what brake pad wear they've had and what mileage they have done?
 

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My I3 REX was in for its first service a couple of months ago (8000) miles and brake wear was assessed as minimal. When in traffic, I do set ACC which does seem to use more brake than one pedal driving.
 

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48k no more than 50% wear at return to BMW. Bare in mind the i3 pads are thinner out of the packet.

Brakes are pulsed at first start and drive of the day, manual recommends giving them a regular touch to keep in good condition.

There has been some confusion on vehicle inspection reports as they don’t have the correct starting depths set.
 

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Hello Jack,

Many thanks for your reply. It would be helpful to know what the depth of the front pads are out of the packet. Have you any idea? I thought the front pads would have to be thicker than the rear pads.
 

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Similar story here. Mine went in last week for fuel line recall. I don't drive like a saint but the vast majority of my driving is one pedal and much of it is motorway / A road, not stop start urban anyway.

Service notice recorded 50% front pad wear after 15k miles of hardly touching the brake pedal, which frankly I find astonishing. Not as astonishing as those eye watering prices though :eek:

In contrast, my 2 tonne AWD Kuga without regen had new pads at 37k miles.

I think they've got the measurements all to c0ck! Are the front and rear pads the same part by any chance?

Edit - EBC replacement front pads = £25. So £225 to fit them? They need to train their technicians to work faster! Think I'll be experimenting with DIY for that price.
 

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Discussion Starter #9 (Edited)
The front and rear pads are different, the fronts start with 11 or 12mm, hard to get an exact answer, but it's within those two figures. my pads are at 3mm, wear indicator has not gone off yet. My own experience in cars (which is not small) would lead me to replace my pads now or in the next 1000 miles.

They did mention badly corroded disks, but I have inspected them and it's cobblers, they simply looked at disks that had not had the brakes applied, a few good applications before I got home and the disks are fine with zero wear ridge and virtually no corrosion or pitting.

48k no more than 50% wear at return to BMW. Bare in mind the i3 pads are thinner out of the packet.

Brakes are pulsed at first start and drive of the day, manual recommends giving them a regular touch to keep in good condition.

There has been some confusion on vehicle inspection reports as they don’t have the correct starting depths set.
My dealership knows how thick they are to within 1mm, I do give them a regular touch as far as I can remember and the car is garaged. Also it's indisputable that on some cars and it seems the more carefully driven ones, they are wearing excessively.

I always wondered why the 2000 Honda insights regen braking progressively cut out completely at around 10 or 15 mph (from memory), now I know why, those clever little engineers at Honda. I always thought it was because the IMA system wouldn't generate power below those speeds, but 80,000 miles and less than 50% brake pad wear would seem to indicate BMW needs to take a leaf out of their book.

I also now expecting the new leafs to have a similar problem, unless some cleverness has been used.
 

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Thanks to all for your information and thoughts.

I went into the dealership today to raise the issue of the Vehicle Health Check attached to the fuel vent pipe invoice which quoted the depth and wear of my Front and Rear Brake pads. I was very well received and immediately I was told that it was not possible for 8mm depth to give approximately 42% wear. The front pads out of the packet are only 10ish mm in thickness. My car was put up on the ramps and the Workshop manager showed me how the brake pad gauge was used and the readings on my pads. Apparently the technician would have read off the gauge 8mm and 10mm respectively and the software would have supplied the % wear, but on the basis of a Series car, not an i3. BMW haven't done the software yet for the workshop in respect of the i3. Further 8mm and 10mm is perfectly respectable for my car.

You can tell I'm not a mechanic, but I hope you are following the gist of what I'm saying.

So you can perhaps ignore the reference to the % wear, and only look at the quoted mm depth.

Further both the front and rear brake pads are the same depth, but the rear pads have a smaller area.

So, if like me you have concerns about the quoted health of your brake pads I suggest you go back to your dealership and let them explain it to you.
 

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So the pads on a LEAF taxi last 100k and the pads on a light i3 last 30k with one pedal driving, something doesn't sound right, either the pads are incredibly soft or there is an issue.
 

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Discussion Starter #13 (Edited)
So the pads on a LEAF taxi last 100k and the pads on a light i3 last 30k with one pedal driving, something doesn't sound right, either the pads are incredibly soft or there is an issue.
The issue is 1 pedal driving, I think BMW need to progressively, but fairly quickly reduce regen to 0 at speeds of say 15 mph and have the computer use the brakes to bring it to a stop, necessitating the brakes to be used. I am sure they could and should code this into the software.

My old insight which did this (well regen stopped and I personally had to use the brakes) would have given me over 150K on the pads, as it was, it gave 80K with only 50% wear.

As for @LadyRex even 2mm pad wear on 10mm pads in 2k miles (and i think they are actually 11 or 12), but lets say they are 10mm, at 1000 miles per mm, that's still only 8, perhaps 10K miles before they are at 2mm, at which point you would have to replace them. lets say you manage to go twice as far, 20K, that's still a ridiculous pad life for a car that doesn't really use it's brakes anywhere near as much as "normal" cars.

Surely something is wrong, it's just illogical to think otherwise.
 

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Does anyone know why it's so expensive to change the pads, I changed the discs and pads on my Passat for £60 so the figures that are being quoted for just pads are extortionate to say the least.:mad:
 

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Does anyone know why it's so expensive to change the pads, I changed the discs and pads on my Passat for £60 so the figures that are being quoted for just pads are extortionate to say the least.:mad:
ETK shows pads as being around €65 for the pad €25 for sensors, thats for a pair of pads but 1 sensor.
 

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ETK shows pads as being around €65 for the pad €25 for sensors, thats for a pair of pads but 1 sensor.
They must be standing around admiring the car for a couple of hours before they actually start work on the damn thing to get to those prices then.
 

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Just checked the healthcheck when I had the pipe clip done - along with the REX power cable (which was causing errors - all sorted) and I see

Front - Brake pads - 7, Disc (r=1, a=2, g=3) - 3. Read -0 Brake Pads - 8

My tyres were shot though all around (just under 2mm across the board), but thankfully sorted quickly via leasing company . Surprised at that very even wear
 

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I Took mine in for the petrol pipe recall as well. About 8500 miles and very surprised at the tyre and brake wear. Not driven hard by any stretch of the imagination. Tyres mostly at 4 mm tread. One part of two tyres at 3mm and "advisory". Front pads at 6 mm "advisory" and rear pads at 9 mm. Although these would be considered "consumeables" surely this is some form of design or manufacturing fault (or mis reading procedure as above). With this type of wear should the first service be at 12 months rather than the 24 months standard ? Very poor indeed. I expected more from BMW.

Richard
 
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