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I’ve given up driving in L and use D all the time, now. The efficiency loss is far less than the cost of a brake job.
I will again point out that your brakes don't really get any more use in D mode than they do in L mode. The car will use regen to slow down when you push the brake pedal in D mode, up to the regen limit of 66kW.
 

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I will again point out that your brakes don't really get any more use in D mode than they do in L mode. The car will use regen to slow down when you push the brake pedal in D mode, up to the regen limit of 66kW.
So should we be doing a quarterly panic stop on a deserted road or something to make sure we use / lubricate these parts?
 

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So should we be doing a quarterly panic stop on a deserted road or something to make sure we use / lubricate these parts?
Well I used to say that you could fill the battery to 100% so that it can't accept any significant regen and then do some stops while going down a hill. But now....?

I guess you could get up to speed, put the car into "N", and then hit the brakes.
 

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So should we be doing a quarterly panic stop on a deserted road or something to make sure we use / lubricate these parts?
A hard stop heats the Pads and Discs. "Beds them in" in racer terms...
Nothing it being 'lubricated'.

These single piston calipers 'float' on lubricated slider pins. Most cars have floating calipers.
As the pads wear and get smaller the caliper is now on a different area of the slider pin.
When the rubber boots let in salty winter slush, the pins and caliper can start to rust and not slide/float freely.
 

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Discussion Starter #25
A warning for anyone else attempting a brake job on these. The back calipers have to be calibrated if the pistons are compressed. I guess there is a link to the stabilitrack computer. The front calipers do not have any sensors on them so compressing them does not effect any electronic system. My rear brake pads were barely worn so I just put on new rotors that were within two thousands of an inch thick of the old rotors. No codes and brakes are all working smooth
 

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I’ve been taking at least 2 long trips per year with my ICE cars for the past 25 years, and even living in the Southeast - when I return, the undriven vehicles have rust buildup on their rotors. The first time I take off with each of them I get that terrible rusted/grinding noise like the brakes are totally gone, but just applying the brakes a few times knocks all that crud off.

Sounds like the Bolt needs a “Maintenance Mode” to accomplish the same kind of thing.
 

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A warning for anyone else attempting a brake job on these. The back calipers have to be calibrated if the pistons are compressed. I guess there is a link to the stabilitrack computer.
The calibration is debatable. It's not just the Bolt, but a number of other cars have rear brakes with E parking brakes and a calibration function. The number of posts in various forums on the need to calibrate after a brake job is mixed, with more leaning towards calibration not needed post brake work. It seems like it's something that needs to be monitored and then a calibration should be done if you notice any issues. Of course, if you don't know what to watch for, and you did the brake work yourself, you should get the calibration done.
 

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Discussion Starter #28
I’ve been taking at least 2 long trips per year with my ICE cars for the past 25 years, and even living in the Southeast - when I return, the undriven vehicles have rust buildup on their rotors. The first time I take off with each of them I get that terrible rusted/grinding noise like the brakes are totally gone, but just applying the brakes a few times knocks all that crud off.

Sounds like the Bolt needs a “Maintenance Mode” to accomplish the same kind of thing.
If you noticed my pictures above there was no wearing the crud off, the rust is deep.
 

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Discussion Starter #29
The calibration is debatable. It's not just the Bolt, but a number of other cars have rear brakes with E parking brakes and a calibration function. The number of posts in various forums on the need to calibrate after a brake job is mixed, with more leaning towards calibration not needed post brake work. It seems like it's something that needs to be monitored and then a calibration should be done if you notice any issues. Of course, if you don't know what to watch for, and you did the brake work yourself, you should get the calibration done.
I figured it had something to do with the E brake mechanism but I’m not sure what to look for. If you don’t have to put in new pads I don’t think it senses any change.
 

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So what do you watch for?
Listen for any dragging or scraping sound. Does it feel different when starting to drive? Any pulling? Do temp checks on the brake rotors; you'd want to use and IR temperature reader and you're looking for significant difference between the rotors on the same axel/part of the drivetrain. The last one is a smell test. No, you don't need to stick your nose in the wheel like you're taste testing a glass of wine, but excessive dragging of the brake can produce some off smells.
 

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Listen for any dragging or scraping sound. ..... The last one is a smell test. No, you don't need to stick your nose in the wheel like you're taste testing a glass of wine, but excessive dragging of the brake can produce some off smells.
If you wait until there is stink,, you've driven too far after doing something wrong.
 

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If you noticed my pictures above there was no wearing the crud off, the rust is deep.
Yeah, but it didn't come from the factory that way. What I was saying was ... if you had an override of the Regen function to allow the brakes to operate "normally", you could occasionally "clean" your brake disks and maybe avoid that rust problem all together.
 

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... if you had an override of the Regen function to allow the brakes to operate "normally", you could occasionally "clean" your brake disks and maybe avoid that rust problem all together.
You do have such a function! It's shifting to N and braking hard.
But when the sliders get rusted into place most of the braking takes place on one side of the disc.
 

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You do have such a function! It's shifting to N and braking hard.
But when the sliders get rusted into place most of the braking takes place on one side of the disc.
OK, but that's not a "function" of the vehicle, that's an inelegant, 'under-the-radar' workaround. A "function" would be the vehicle either having the 'disable' switch, or just being smart enough to know when it's time to turn on the 'rotor cleaning' function.

And "rusty sliders" is not an EV problem, it can affect any vehicle.
 

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1<... or just being smart enough to know when it's time to turn on the 'rotor cleaning' function.

2<And "rusty sliders" is not an EV problem, it can affect any vehicle.
1< That would then have to be incorporated in EPA testing, which would only lower that range number.
2< This is very, very true.
 

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Discussion Starter #37
There is definitely a little more brake action in drive than low so I’m using drive now. Every spring I’m going pull the pads and guide pins to clean and grease. The rust was not even close to bad on the face side of each rotor, the back side looked much worse on all of the rotors. You can put it in N and brake it on a hill but the manual says don’t drive in neutral. Maybe if you don’t do it for long distances it won’t damage anything. I’ll certainly be looking at the back side of the rotors more often now.
 
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