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Discussion Starter #1 (Edited)
Getting state inspection now, rear brake rotors will need to be replaced (5 year+ age since production, 73k miles on the odometer).

The Volt is too good. The non-use of brakes has caused me to need new rear brake rotors due to heavy rust build-up on the rotors. Due to non-use.

A few here have said that one good tip is to use Neutral down a long hill and "scrub" the physical brakes every couple weeks or more. That keeps the surface rust from building up and the price is very mild wear.

My disks look like the walls of Carlsbad Caverns with 2-3mm thick bumps of rust.

The Volt's electric motor regen braking (and my lack of aggressive braking) is so good it requires parts to be replaced after non-use. Front disks look fine - must be slightly used somewhat versus the rears.

Regarding sustainability (and economics) we do need to face issues such as this so that parts that are unused actually not not "rot away" under normal conditions.

We have the engine maintenance cycles to run the engines every so often if not used. Could we have a brake use maintenance cycle as well? Of course, it's easy to throw it into Neutral to do some braking activities from time to time.
 

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I had to replace one of my rear rotors and caliper on my 2011 Volt for the same reason. It was corroded and frozen up due to non-use. Only 26,000 on the ODO,
 

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In my environment it nearly impossible to completely avoid an occasional hard braking event. Besides the rotors aren't hard to see nobody even looked at them in 70k+ miles?
 

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Discussion Starter #5
In my environment it nearly impossible to completely avoid an occasional hard braking event. Besides the rotors aren't hard to see nobody even looked at them in 70k+ miles?
Passed inspection last year but probably was "close" and they just didn't care to warn me to try to find ways to keep the rust from accumulating. No big deal. Now, my "iron footprint" for owning the Volt has gone up a little. Carbon footprint still moderately low.
 

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I'm on the fence as to whether I should do that shift to N trick every once in a while. Under normal driving, brake pad contact happens when braking in reverse and while stopping. I find myself doing a lot of "rolling stops" at stop signs where my speed does not drop below 5 mph (meaning no brake pad use at all). I'm in very rural areas with nobody around for miles, why come to a complete stop?

Theoretically, if you do all rolling stops, the only time you actually use brake hardware is when you reach your destination.
Luckily, my commute has a few traffic lights that force me to actually stop. I can feel/hear the pad contact as I stop.
 

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Getting state inspection now, rear brake rotors will need to be replaced (5 year+ age since production, 73k miles on the odometer).

The Volt is too good. The non-use of brakes has caused me to need new rear brake rotors due to heavy rust build-up on the rotors. Due to non-use.

A few here have said that one good tip is to use Neutral down a long hill and "scrub" the physical brakes every couple weeks or more. That keeps the surface rust from building up and the price is very mild wear.

My disks look like the walls of Carlsbad Caverns with 2-3mm thick bumps of rust.

The Volt's electric motor regen braking (and my lack of aggressive braking) is so good it requires parts to be replaced after non-use. Front disks look fine - must be slightly used somewhat versus the rears.

Regarding sustainability (and economics) we do need to face issues such as this so that parts that are unused actually not not "rot away" under normal conditions.

We have the engine maintenance cycles to run the engines every so often if not used. Could we have a brake use maintenance cycle as well? Of course, it's easy to throw it into Neutral to do some braking activities from time to time.
Instead of dangerous games, just use the brakes more. I can't imagine a daily driving routine which does not cause you to use the brakes at least a few times per drive.
 

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Mine stay clean from normal daily driving. I don't need to shift to neutral. And that is with pretty gradual braking, not rapid stops. But I do have plenty of traffic lights that require full stops. I wonder if there is something wrong with your brakes if the rears never touch the rotors. It should take very little to clear the rust if it is done frequently.
 

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My wife scares me into hitting the brakes hard all the time while she is driving from the passenger side. I guess that is the net benefit aside from preventing a real accident from time to time!
 

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Maybe the computer should institute a "Brake Maintenance Mode," wherein regeneration is shut down periodically for a while until the brakes get used enough to keep them clean. Just a few lines of code...
 

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If it's just the rears, perhaps using the parking brake would help. I understand that under emergency conditions one can pull and HOLD the parking brake switch to engage the parking mechanism in the back and it will hold until released. I would highly suggest ensuring plenty of room behind you when trying that. Perhaps in a vacant parking lot and lower speeds? That should clean up the rotors and pads efficiently.
 

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Mine are still looking good. A 2011 with a few more miles than yours. And I live in the land of winter salt.
 

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No pictures, but I find it hard to believe these rotors were bad. Frozen calipers or a dragging parking brake maybe. But not rust. If they are above the minimum thickness and don't shake they should be good.
Rotors are wiped off when the car is braked in reverse. I wouldn't try any high speed panic stops in Neutral. It's dangerous and you can't do it enough to make any difference.
 

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Discussion Starter #15 (Edited)
No pictures, but I find it hard to believe these rotors were bad. Frozen calipers or a dragging parking brake maybe. But not rust. If they are above the minimum thickness and don't shake they should be good.
Rotors are wiped off when the car is braked in reverse. I wouldn't try any high speed panic stops in Neutral. It's dangerous and you can't do it enough to make any difference.
I am not saying antics or danger. I am saying "light, gentle braking down a long slope with nobody around while in Neutral". This is actually what every single car on the road (besides hybrids and EVs) do all the time. I simply mean to actuate the real brakes rather than rely on the regen.

Regen works all the time and I drive with traffic but do not slow hard (which is why I had 73,000 miles on my tires when replaced).

The rotors were very rough on their inner edge. the tech at the shop showed me the state inspection page which requires not-passing if they were in the condition they were in and I kind of went along with it. Other than spray chain lube on them monthly to keep them oiled up and free from rusting - I will try some occasional neutral braking in a safe manner to see if I can see a little bit of wear put on the new rotors.

The money spent babying my tires, smooth driving and caring about sustainability was then spent on new rotors. Oh well.

One last thing - this was done at a Honda dealership. The first thing the lady did when she came out for the "hey, you got a minute?" talk was to say that the tech said the rear rotors where "thin and rusty and won't pass inspection". I said "thin? I don't use them..." The tech showed me in detail the rotors and I said the writer told me you said they were thin - he said "no I never said that".

I know that dealers work-over the customers (it's their job to up-sell) and I heard the the writers telling other customers about their brake wear levels in the shop - was pretty busy due to last day of month inspections and so on. I really do think I could have taken it elsewhere and possibly passed. But the state paperwork says that they should not pass heavily rusted brakes. They did look like a car parked in a yard for a couple years and I didn't really mind too badly how it worked out. But honestly, the front rotors still look like new and I do think something went wrong with the rear rotor anti-rust treatment at GM such that they developed as much as they did. Do not 100% trust service writers like some of the zombies I heard agreeing to work being done in there. Verify their claims and force them to prove the problems. I heard numerous times "see you in 5000 miles for another oil change". I really was too busy working on my laptop to yell "get a plugin!" to all of them. Dealers are going to be very hard to "convert" to the EV landscape. I think it is going to take a very long while to get people to make the change en-masse.
 

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A question and comment...

I've never seen definitively on the Volt that friction brakes are used in reverse and under 5-6 MPH. Is this documented somewhere?

It would make sense with my wear pattern as I have a significant reversing event every day and have never seen anything but light surface rust and dust on my rear rotors the day after rain or snow events.

I think folks are overreacting to how dangerous neutral slowing/stopping is. Every manual transmission driver on the planet has likely stopped from the speeds we're talking about without downshifting from time to time. This is exactly the same thing.

For the purpose of cleaning the dust and surface rust off the rotors, there's no need to panic stop. I don't think anyone is advocating that you duplicate the Car Magazine 60-zero stop tests to see if you can still stop in under 200 feet. You could just ride the brakes down a hill if that's an option where you live. What's important is that you NOTICE on some routine basis, say monthly or every few thousand miles so that the pitting doesn't get a foothold. It's especially important in brining and salted road climates.
 

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A question and comment...

I've never seen definitively on the Volt that friction brakes are used in reverse and under 5-6 MPH. Is this documented somewhere?

It would make sense with my wear pattern as I have a significant reversing event every day and have never seen anything but light surface rust and dust on my rear rotors the day after rain or snow events.



FWIW: Example pics of my front & rear rotors on my Gen1 back @50000 miles.

I believe this Volt rotor rusting issue has to do alot more with climate and what type of road salts are used rather than driving technique since I just drive normally in (L) w/o performing any panic stopping or braking in reverse. I usually just shift from a slow roll in (R) straight into (L) without stopping to use the brakes cause you can do this on the Volt with no issue!;)
 

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FWIW: Example pics of my front & rear rotors on my Gen1 back @50000 miles.
I was going to post a picture of mine, after almost 5 years and about the same mileage, but it would be the same picture. The rotors still look like CDs. I don't use 'L', my wife does, so about 50% each way. I did have the calipers 'serviced' once because I was worried about them locking up for lack of use and lubrication.

No good theories why the OP's are so much worse, unless they've suffered some kind of abrasive damage to ruin the nitrided surfaces. Sand or gravel getting under the pads?
 

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Whoever did the ten tire rotations didn't inspect anything? Even Discount Tire has warned me about potential deficiencies during tire/wheel work.

There had to be some wear on these parts to wipe out the nitrile coating on the rotors.
 
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