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Does regenerative breaking help to SAVE break pads??

Does regenerative breaking help to SAVE break pads??

I've seen recent posts to suggest this. I was under the impression that while regen breaking was very good for increaseing range, it actually "wore" the pads more since the MS ends up breaking more than an ICE car...just by lifting off the accelerator. (I thought my DS had told me this.) The posts I've read suggest that I was mistaken?? If so, fantastic. Can someone please confirm?

Btw, does TM suggest how often (# miles) the breakpads would be expeced to last under "normal use"? Thanks for your help!

AmpedRealtor | 28 octobre 2013

Regen slows the car through the motor, it does not use the brake pads at all. Brake pads are only used when the brake is applied, which is separate from regen. My Prius was on its original brake pads at 123,000 miles with usable life left. I offer that information because the Prius also uses regen.

201w77 | 29 octobre 2013

Thx AmpedRealtor! Appreciate it.

Car t man | 29 octobre 2013

Even though its a sport car, your pads will last you a very very long time. An electric motor also acts as a generator when it is used for slowing the car down, storing the energy in batteries rather than losing it as heat through friction between brake discs and brake pads. Much more efficient and saves your pads.

mumanoff | 29 octobre 2013

BEST OF ALL: NO MORE BREAK DUST !! YIPPEE

chrisdl | 29 octobre 2013

201w77:
Just make sure to set regen to "Normal".
With regen set to "Low" you may wear out your brake pads faster than a bunch of forum posters learning how to spell brake.

Brian H | 29 octobre 2013

Especially try to avoid break dust. Brake dust is messy, but ...

Earl and Nagin ... | 29 octobre 2013

We have an '08 Roadster with over 60K miles on it and less than 20% brake wear. I think that should be good enough evidence to confirm.

Roamer@AZ USA | 29 octobre 2013

As a car guy who loves mechanical devices it is heaven to slow down electromechanically.

I no longer feel the agony of riding when my wife drives and the pain every time she accelerates just to hammer the brakes. I can feel the calipers closing the poor helpless pads onto the rotors and the extreme heat and dust being produced as all the mechanical parts undergo the stress of wasting all that kinetic energy and converting it to heat.

It is a pure zen like experience to feel the gentle and pure application of magnetic fields pushing gently against each other in total harmony as they gather up that kinetic energy and place it gently back into the batteries.

Regen braking is a holistic experience for those of us that visualize every mechanical component as it is operating.

The only time I use the brakes on the Tesla is the last 5 MPH to come to a complete stop. Better than.......well not quite.

robert | 29 octobre 2013

@Roamer

How poetically said - and how true. Bravo!

Robert

Garth | 29 octobre 2013

Regen breaking drastically reduces wear on the brakes (as stated above), but I suspect the rear tires may experience more wear from being torqued by the slowing motor... I don't have evidence to back that up, it's just my speculation.

TikiMan | 29 octobre 2013

If you ever drove a manual transmission ICE vehicle and always down-shifted to help slow down (rather than just breaking in gear), you likely noticed that your break-pads lasted much longer.

In the MS, it very similar, except it's automatic, and completely smooth.

mrspaghetti | 29 octobre 2013

@Tiki

Did you ever notice increased wear on rear tires from downshifting? I'm guessing not, but maybe I'm wrong.

nomoDinos @ca.us | 29 octobre 2013

Garth - I've heard a Toyota engineer talk about that, he confirmed that it would probably increase wear over time.. That's one reason I was interested in the AWD - if regen was applied to both the front and rear, it might even out the wear.

Chrisdl - "Brake yourself before you break yourself", is what my driving instructor told me. Also sounds vaguely similar to some old rap lyrics.

Rheumboy | 29 octobre 2013

That's why the signs tell truckers to use their gears and not their brakes to slow on steep grades. The ones that don't end up on the runaway ramp.

chrisdl | 29 octobre 2013

Garth:
Slowing down by turning kinetic energy into heat to reduce a wheel's rotational speed or doing the same by turning it in electricity does not make a difference on the tires wearing out. In fact, with normal brakes you're more prone to block a wheel or activate ABS which will wear out your tires faster than the smooth regen braking.

JPPTM | 29 octobre 2013

Sort of a related data point---I sold my 2009 Lexus GS450h when I got my S. I drove it 4.5 years and it had about 80k miles. High performance (0-60 in 5.8) and I drove it hard. With the Toyota/Lexus hybrid system and the regen braking as implemented, I had only 20% front brake pad wear (and nil rear brake wear). I would expect that the Brembo pads on the S will last a long, long time if you use Standard regen. YMMV.

Roamer@AZ USA | 29 octobre 2013

Tire wear may actually be improved. Hard braking puts more load on the front wheels than rear as the vehicle weight distribution shifts forward.

Regen slowing would obviously put a little more wear on the back.

Regen could provide balance.

nomoDinos @ca.us | 29 octobre 2013

Garth - sorry, I wasn't clear. Regen would increase rear wear RELATIVE to the front (with regen on the back), but it would be less than brakes would cause.

Need more coffee.

DTsea | 29 octobre 2013

@garth is correct, TM says the rear tires wear faster- both due to regen (when brakes are used, all four tires slow the car, but in regen only the rear tires are involved) and because the car is rear wheel drive.

That's why tire rotation is recommended at 6000 mile intervals, which is quite frequent.

chrisdl | 29 octobre 2013

Two different duscussions are mixing up in this thread:

1) rears wear our faster than fronts, due to acceleration and, to a lesser amount, regen

2) rears wear out less from regen than from regular brakes

Sofie S. | 30 octobre 2013

If you drive too carefully, you might have to change the brakes beacause of rust not the wear.

Car t man | 30 octobre 2013

The regen's impact on wear is minute in itself. It can only enhance and already existing misalignment issue in the rear, if anything. But the
appropriate response is to fix that issue, not use less regen. Regen
is way too mild to wear the tires. Acceleration is what causes 90% of
it in normal circumstances and probably about 30% if you have alignment
issues. Those are what pulverizes tires. They need to make a more systemic
and permanent solution for that.

Mark E | 30 octobre 2013

I drive a manual 928 and use the gears to slow the car most of the time - I do not drive slowly, but don't ride the brakes. The last set of pads lasted 230,000km. I'd expect regen would have a similar, perhaps better result.

Car t man | 30 octobre 2013

@Mark

using engine braking is the proper braking procedure (even taught in driving schools) for manual gearboxes. It does increase brake pad life substantially but it does increase clutch wear somewhat also. A bit of a tradeoff..

Even when I drive an automatic, I often drive them in manual mode and use
engine braking (if the car has this poorly set up) and hypermile :)

I even did it in an Aston martin and saved some 5l/100km in city driving but
would advise against it because they aren't very durable and the gearbox
costs a fortune.. So depends on the car. Porsches are much more durable,
so it shouldn't be a problem. Just can't remember if the 928 is the one
standing out for above or below average Porsche durability?

Pungoteague_Dave | 30 octobre 2013

I am always amazed that people who are educated enough to afford a Model S yet don't know the difference between breaks and brakes, breaking and braking, etc.

To the OP - you can edit the title on original posts by hitting the top left of the post, where an edit handle will pop up.

Rheumboy | 30 octobre 2013

PD...give me a brake!

BarryQ | 30 octobre 2013

Hoo seys u hav too b edumcated 2 bye a modil S?

Car t man | 31 octobre 2013

Often times it is the auto correct which screws people's posts. Depending on device used, mine screws up everything me continuously..
One more reason for the need to have an edit function..

Brian H | 31 octobre 2013

Yeah, and some want autocorrected autos? Bad idea.

Mark E | 31 octobre 2013

Car t Man:

I've never been worried about the way that I drive being bad for the car - I drive fast but smoothly and can and do heel/toe minimising shock on the transmission and clutch, and minimising brake wear.

My Gt_Four (All-Track in the US) Celica's clutch needed replacement after 200,000km of primarily city driving, using engine braking constantly. My 928 now has 407,000km on it and is a '90 GT that I've owned for 13+ years as my daily driver here in Sydney NSW. I have put 2 clutches in it during that time - pretty good in city traffic. At 343,000km my mechanic removed and rebuilt the engine pre-emptively. There was no appreciable wear anywhere in the engine. The heads were sent to be reconditioned but were returned after simply being cleaned as even the valve guides showed no wear. The bores and pistons, were perfect, and all that was done was new rings, bearings, various bolts and gaskets were fitted.

There are lots of people with 'helpful' information about 928s, 944s and 924s. Most are completely wrong, including people telling me my car was a flat 6, that the engine was from an Audi, that they were terribly unreliable etc etc. Here in Australia the 928GT was $AU236k (in those days $US180k) plus on road costs in 1990. Unfortunately many current owners cannot maintain them adequately or use the wrong oils in them killing them.

Its a bit like a Tesla, I have also heard lots of wrong information from 'experts' when they hear that I am a reservation holder, like the 928 'experts' most of the information is wrong.

The model S will be my new daily driver and my biggest worry is that I will be unhappy with the handling and seating support. My 928 is the most impressive car that I've driven other than the roadster, which I considered. The roadster is just too impractical to have as my primary car as my wife's car is a BMW Roadster. It will be hard to give up the 928, I still love it and have not found another vehicle to replace it apart from a V8 Vantage. Since I'd rather buy another investment property than an $AU220k Aston I've kept the 928 for a very long time. I've been waiting for my Tesla as a reservation holder for nearly 2 years now! The price rises combined with the currency fluctuations have increased the price of the car by 20% (ouch).

Back on topic... drive sensibly and use engine braking and your brakes will last a long time. :)

BattBoy | 31 octobre 2013

2nd that Mumanoff! No Brake Dust. After driving my MS for 6 months, I finally noticed a bit of brake dust that didn't wash off after just a spray off-wash. Huge difference between normal regen braking and standard ICE braking.

Car t man | 31 octobre 2013

Porsche in general is very reliable. An Aston isn't. My friend has one as a collector's car and had to have the engine rebuilt at 4 or 5000 miles..

In "super cars" like Ferraris, Lambos, Maseratis etc.. I woud still preserve
the clutch more than pads thought. Reliability is low and costs of clutch
and gearbox repairs very high. Pads are cheap in comparison..

djm12 | 2 novembre 2013

There is a post on the Facebook Model S forum concern a Model S that needed a brake replacement. The owner rents out the Model S as a business and didn't know that regen could be adjusted. My assumption would be that someone renting a Model S would be harder on it than normal owners. Anyone else with an actual Model S experienced any brake wear?

Car t man | 2 novembre 2013

In EVs, ICE drivers still use foot braking predominantly, due to being
used to it. Every time a "civilian" drives one of mine, they do it.

If they rent cars to such "civilians", they will be flooring the car because that's why the rented a Tesla for a day and they will brake like crazy also during such driving, doing most if it via regular brake pads. They then will wear out since it is a heavy and fast car, being abused during a short term
abuse rental..

NKinne | 2 novembre 2013

@mark : you have a 928? I have a 928gt too. Love that car. I will never sell it! When I finally get the x I will sometimes drive the old porsche and enjoy the good old days of motoring. Damn, that's a cool car!

Brian H | 2 novembre 2013

NK;
So say many, but in the end they can't bring themselves to fiddle around in a putt-putt.

201w77 | 3 novembre 2013

@Pungoteague_Dave -- Let me guess...you are single, no friends, and mad at the world. Just trolling around on message boards correcting grammar. Way to go winner! Thanks to the other posters for thoughtful responses to my question. Dave- Keep up the good work as the human spell-check!

Alex K | 3 novembre 2013

@201w77 | NOVEMBER 3, 2013: @Pungoteague_Dave -- Let me guess...

@Pungoteague_Dave is the antithesis of how you have described him. It wouldn't kill you to edit your original post and change BREAK to BRAKE. I cringe every time I see it spelled wrong. It's spelled wrong on this forum so many time (by others), that I'm afraid I will start spelling it wrong too, and then I'll have to cringe at myself.

chrisdl | 3 novembre 2013

201w77:
Hey, what about me?!
Not Dave but I was the first to point out the wrong spelling in this thread. I even beat Brian to the punch this time. Honor where honor is due! ;-)

I admit: I did give some information as well. And I agree with you: Dave's tone was a bit harsh, but I'm sure he meant it well. Besides: it serves you right, you English speakers you. Who invents a language with exactly the same sounding words with different spelling anyway? Homophones!

robert | 3 novembre 2013

@chrisdl

Like "honour", you mean?

chrisdl | 3 novembre 2013

Robert:
I try to use American spelling. Old habit :)

Mark E | 3 novembre 2013

@Nkinne: Yep, mine is a 1990 928GT, Grand Prix White with Cup1 (genuine) wheels. Best long distance car I have ever driven - in fact we drove 1500km non stop, and got out feeling absolutely fine. 2 days later we drove back, also non-stop other than for fuel. The seats are the best. A model S would have taken a *lot* longer for that trip - even when we finally get superchargers here in Australia.

I'm very fortunate to have a local mechanic who was factory trained in 928s and worked at the dealership where mine was sold - he did the pre-delivery on it! You need a specialist to get the most out of them - which is why there are some that are in very poor condition. If you know what to watch for and how to service them, they are very reliable.

I love mine, but may have to sell it as I have only enough space for my wives car, mine and my bike plus workshop gear. It will be missed, despite a Model S being cool and fun.

Car t man | 3 novembre 2013

I think Tesla has an experiment going about how soon people will start killing each other over spelling without the edit function on the forum..

Brian H | 3 novembre 2013

Killing is hard online.

Mark;
how many wives, kids, cats, kits?
(wife's cars)