Hypermiling helped ruin my brakes. Toast after only 25k km / 15k miles
 

Search around and you'll find a couple of posts from me from the past whining about how my front brake rotors are always rusting up because (1) I don't drive my car much, and (2) when I do, I don't use the brakes very much/very hard.

To try to solve this, I actually got in the habit of trying to clean the rotors off by stopping pretty hard ... on those rare occasions that I do have to do "normal" braking.

But the rust apparently got further ahead than the pads could scrub clean, and the result is I've now worn the pads down to the wear indicator on the rough rotors!

Here's what they look like now:

http://ecomodder.com/forum/attachmen...1&d=1246912155

Makes me think that cars with regenerative braking will have the same problem - possibly more than regular cars.

These may still be OK to be machined down; I haven't looked into it yet.

Looks pretty ugly Darin. Gotta do some preventative maintenance on your car!

Sorry for the lousy pic: the pitting is pretty significant. Sand paper is not an option.

Vaseline on the rotors!

You don't use the brakes anyway though, so what's the big deal? ;)

Ouch!

How about adding ~200 lbs to the car so you use your brakes harder?

Those look pretty gnarly. Take them to a brake-turning place, there may be hope for them yet.

I personally think it's not so much the hypermiling as you not driving your car frequently. If I remember right, you can go a full month without using your car. Time is rust's best friend, it lets it work its ways.

Is there something you could spray on that prevents rust, but does not interfere with brake pads? That sounds like a tall order.

BTW, What do the rear drum brakes look like?

I told you about WD40 right?

Yup, I bet 4 wheel drums would look just dandy.

I just got through unsticking (derusting) some Metro front brakes. Not only was the rust building up in the grooves for the piston seals and dust seals, pushing them against the pistons so they wouldn't retract, but the pad cradles had rust under the stainless pad seats, pushing them tight to the pads so they weren't free to move either! :mad:

I hate disk brakes on cars.

On yer disks tho', having them turned would likely get rid of most if not all the pits.

I pretty much never have rotors turned, only because they're so cheap to buy new. Turning them takes away heat dissipating material (although making them slightly lighter), thus making them more prone to warpage that one time you actually do have to stand on them. (Deer and bear don't stop for you around here.)

That does look pretty crappy, though... might be a good idea to spray them with WD-40 once a week or something to keep that from happening.. As soon as you touch the brakes, the lube will burn off and you'll have braking power.

McTimson: a philosophically interesting question. I've still got rear brakes...

Martin: I agree, it's probably more the lack of use than the light braking. Come to think of it, having spent the winter in the salt air of the east coast must have been extra hard on them. I had to oil my bike chain on the beater bike about twice a month all winter to keep it from rusting solid.

I'm a slow learner Frank. Seems it has to cost me money before I learn my lesson :) But after I replace/machine these rotors & change the pads, I will try WD-40 if I know I won't be driving for a while. Of course, smooth wheel covers complicates things a bit...

Now you just need to devise a nifty wd40 spray distribution system...

I had a really strange failure on the metro too, I just attributed it to cheap rotors. I had one quarter sized pocket of rust that was about 1/16 inch deep on one side of one rotor.

The "cheap" rotors are like $18 apiece and take an hour or so to change so I'm not gonna pine over your situation too much :)

Friction brakes should be phased out. Hub motor/regens all the way.

Brake pad material should also be considered. It might be worth your while to investigate more specifically how brake pads and steel rotors interact, and what a warped rotor really is.
If you're rarely using brakes, but when you do use them it's fairly hard, a soft organic compound is not the best match. If you're light on the pedal with occasional hard braking, an organic compound would suit better than a semi-metallic or full metallic.

Anyways, do some research on braking systems, and find what suits your needs best. While 25K isn't bad for some applications, you should easily exceed 150K (km that is, in case anyone wasn't pay attention) for the use your car sees. IE, the brakes should fail after the rest of the car does.

WD-40 on brakes? Do the bad ideas never stop around here? :rolleyes:

Just how would that keep you in position on a hill without using energy? Answer: it wouldn't.

Hi Metro, sorry to hear about the brakes. Perhaps you should brake a little more. If used lightly during DFCO you might only lose a tiny amount of mpg.
I dunno what kind of wheel covers you have but moon discs could help keep the corrosive breeze off them while parked. Could also offset the decrease in mpg from the extra braking?

ollie

almightybmw - good points. It makes me wonder where the OEM pad material lies on the hardness scale.

vtec-e: car has smooth wheel covers, so the corrosion was more from ambient conditions, not really from moisture/rain blowing in on the wind. (At least on the outside surfaces.)

Shawn D: just curious, anything constructive to add?

I wonder how RV owners deal with rotor corrosion (since their vehicles often sit for long periods). It's common to see their wheels/tires covered when they're parked outside, but I suspect that's more about protecting tires from UV damage. Then again, they undoubtedly brake MUCH harder when they are used, and the pad area is larger so would scrub the rust off better.

On this topic, in another thread Frank quoted a newspaper article about storing a vehicle:

"Constructive" doesn't only mean "positive response," you know. Saying something is a bad idea is constructive when it's a bad idea that folks should be steered away from. The linked article also says you should put a tarp under the vehicle when stored in a garage -- that particular piece of advice won't be harmful, but it's worthless. Bob Sikorsky's "Drive it Forever" column actually printed a reader tips about saving money that included salvaging plugs, filters, and even brake fluid from cars in a junk yard -- there's plenty of auto advice that's not fit to print or follow.

Given the corrosion on the other non-friction surfaces of the rotor (hub, outer edges) and knowing your location, rust seems inevitable. You probably wouldn't be interested in attempting cryogenic treatment, as that's $$. What I would suggest (and it's not something you asked about) is to apply a very thin (and I mean really thin) coat of anti-seize to the hub of the rotor where the wheel sits. That'll keep the wheel from sticking.

Do you have any information that a film of WD-40 won't "dissipate from the rotor with the first applications of the brake"?

(EDIT: of course, assuming a fairly aggressive application, enough to generate heat)

Do you have any information that a film of Crisco won't "dissipate from the rotor with the first applications of the brake"? If not, that must mean it's perfectly safe to use too!

I would get those rotors machined instead of buying new unless they do get to thin, the minimum thickness of them that is stamped in the side takes in to account the heat dissipation and so on and in my opinion it's better to use up a part that is of good quality then to replace it with a new Chinese made part, turning rotors around here costs $15 each, new ones around here are $28 each (for my civic), I'll stick with my old rotors that are rusty enough to make yours look like they belong on a show room floor.

Shawn D: your response implied you have some information that the author lacks. I was only looking for it. Thanks for elevating the tone of the discussion.

Contaminated brake pads are UNSAFE. What is hard to understand about that?

I much prefer disc brakes. I have had enough drum brake problems that I converted all my a-bodies to rear disc using parts from the 84-88 6000 STE. I also converted both my trailers to custom disc setups I designed. Drum brakes trap water, salt, mud, everything and all the little springs and parts corrode, break, refuse to self adjust, etc.

My Celebrity sits all winter, my 6000 sits most of the summer, and I don't have disc problems like that. Even the 6000 snowplow wagon doesn't, and the brakes on that only get used when I plow my driveway in the winter. It sits 99.5% of the time. However all my pads are semi-metallic. It might be worth looking into if you don't already use them. My trailers have organic pads, but like you said eariler, they do brake much harder when they get used. Still, I have never seen corrosion like that even on those rotors.

When I do replace the rotors, I always just buy new. Around here it is $25 a piece to have them turned, new ones are less than that, plus my vehicle isn't out of commision while waiting for them to do it.

So in the absense of actual information about the effect of a light film of WD-40 on the brake rotors - aside from a dramatic warning from Shawn D, a newspaper article suggeting it's OK, the same tip on the WD-40 web site, and numerous references to people using it when putting cars up for storage - I tried it.

Here's my experience, on a car with clean/smooth rotors, with only the outboard surface of each front rotor sprayed:

- No perceptible change in braking behaviour, including the first stop (on an empty road), from moderate speeds (70 km / 45 mph) using moderate pressure (not close to approaching lock up).

- The pedal felt neither grabby nor spongy. It did not feel like I was trying to stop on ice.

- The second time I braked, I deliberately tried to see if I could achieve lock up, again braking from 70 km/h / 45 mph. No problem achieving lock up. (Dry, clean asphalt.)

- The film did not "dissipate from the rotor with the first applications of the brake" - at least not from the speeds and the braking pressure I was using. It took a total of five moderate/hard stops in a row before the film was gone. (At that point the rotor was too hot to touch). Maybe if you verged on lockup from high speed, going downhill, to a full stop, it might work in one try.

Is it possible that controlled testing could reveal increased stopping distance, before the film has been heated off? Of course it could. Is it a dramatic difference? I suspect not. (Now feel free to debate the relativity of safety.)

Is it possible results would be different if both sides of the rotor were sprayed? Of course it is. I didn't try both sides.

After trying this, would I personally do this to my rotors if I knew I was going to leave my car parked outside for an extended time? I'd consider it. It's still a pain in the butt though, owing to the smooth wheel covers and accessing the inboard surfaces.

Would I advise anyone to do this? Of course not. It's clearly unsafe.

It is unsafe. I want a bumper sticker for my Metro that says;
"Safety is for Sissies"
But you are a big boy now, make your own decisions. If you are comfortable with it, I am not going to tell you not to do it. (that's the Gubmints job)
I will however, relate a story of when I was younger and just started my career as an auto tech.

Summer,
1978,
I was working as the Mechanic Trainee for an Esso (yes that is the correct spelling) station in Richmond VA.
A "Full Service" service station.
We had a regular customer who fancied himself a practical joker.
We also had a new boy working the pumps, kid just over 16 years old.
Customer comes in (Quite Swiftly)with is relatively new Corvette.
Tells the kid'
"Fill 'er up with premium, check the fluids and...........
My brakes were squeaking earlier, give 'em a shot of WD40, would Ya?"
(Do you see where this is going yet?)
So the kid does just that, I don't know how much he used, definitely used too much.
Customer finishes his purchase, get in the car and takes off like a bat out of he!!. Hits the brakes at the edge of the road and..................
....................NOTHING................
he crosses four lanes of traffic,
cars whizzing by,
every one else brakes squealing,
hits the parking lot of the store across the street,
skids sideways into the retaining island in the lot.
No real damage to the car, flat spots on the tires,
but boy is he pi$$ed.
The kid got fired, I laughed my A$$ off, the customer never came back.

Just a little note on what not to do.

Oh- you've done this? :rolleyes:

They're opening themselves up for serious liability with that one. Sure, it'll protect them (I never said otherwise), but doing so and not removing it and/or contaminating the pads is dangerous.

No, I'm not so blithe as to intentionally contaminate my brakes. One does not have to personally fail or see exactly matching evidence to know an idea is bad.

I think the bad idea is acting like you know for sure when you don't.

By your logic (sic), since none of you know for sure that putting Crisco on brakes is a bad idea, criticizing doing so would be the bad idea in this situation. :rolleyes:

Here's an idea: Use WD-40 for storage, then wipe off as much of it as you can before you drive it after having stored the vehicle.

Nobody said you had to apply it to the pads.
WD-40 is not a very good lubricant. It's a strong degreaser and water-displacer.

WD-40 mostly dries off with time as it contains a lot of solvent, so there wouldn't be much to wipe off after a long period of time.

Which is exactly why I suggested it.

WD-40 was not designed as a lubricant, at all... was designed as a water displacement formula. The oil in it dries into a thin film in a matter of less than a couple days, so if the car is being stored for more than a day, it's just not going to cause a problem...

That on top of the fact that when you get new rotors, they have oil all over them anyway... how many shops do you think actually use brake cleaner to get that stuff off? Sure, it's a liability if you wreck your car due to their negligence in not cleaning the light film of oil off the rotor before installing it, but the fact is, for many years, a large number of "mechanics" have been doing without this step... and there hasn't been any issues that have come to light about it, have there?

Shawn, do you have any anecdotes that suggest otherwise?

Schultz - It's obviously unsafe to lube your brakes... and many thanks to you for that story... actually was quite funny, although I can't figure out if the customer was joking when he asked for the application or not. I also can't figure out why in the world, if he had been joking, he wouldn't have noticed that the kid was doing something through his wheels to apply lubricant to his rotors and pads, but no matter... still a funny story.

The local tire shop I worked in during college removed the shipping anticorrosion coatings, Pep Boys removed the anticorrosion coatings when I worked there after college, and I've always removed the anticorrosion coatings. All of the rotors I've bought lately were not coated with the oily stuff, though -- they were wrapped in anticorrosion paper which does not leave much behind (but which I cleaned off anyhow).

Anyhow, my anecdotes don't fit in with the zeitgeist here, which is "Don't question anything anybody says here, only provide 'attaboys' and cheerleeding" so why does it matter?

Now you're just being (sic).

Hmm... a specific product designed just for this situation AND designed to not contaminate the friction material.

http://img.tradeindia.com/fp/0/179/324.jpg

How do we put someone on "ignore"?

Shawn, if you knew about the product, why not have introduced it a few posts ago? Instead of appearing inflammatory, I mean.

As far as the bold part of the quote... Well, that's just feeling sorry for yourself. I'm sorry, but that's exactly what it is. Saying things like that will get nothing changed, and if you expect to change the way people react to you, that's not the way to do it. But who am I to tell you? You know, I'm sure.

Anecdotes, opinions, and "evidence" based in either situation are not generally accepted as fact. If people just accepted an anecdote as fact, without analyzing and deciding for themselves, I could just tell you that I'm 435 years old, and we know that's not true.

Regardless of what you were taught at any point in life, criticism works in both directions, and simply saying "hare-brained idea" or the like, is NOT constructive, no matter how it's put.

Constructive would be actually adding input, not disparaging the input of others. Saying something won't work can be considered constructive, if you include a reason why. Even if it's just opinion, it's still better than nothing.

Well, you're assuming I knew about it and withheld the information intentionally for trolling purposes. I did not know about it until I Googled on multiple word combinations until it finally popped up.