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Discussion Starter #1 (Edited)
OK, so the brake job saga continues...

Chevy Dealer A told me about two weeks ago that I need to replace the Volt's front brake pads because they were worn down, plus the rotors. Said the rotors cant be turned/resurfaced... because there's a special coating on the rotors. Price = +$600

Now, the car is at Chevy Dealer B up in the burbs getting the transmission fluid and coolant flushed and new OEM tires. They tell me that all four brakes and the pads are fine, with about 50% life or about two years left on them. However the rotors are worn/scored, but thick enough to be resurfaced. The Volt mechanic said even with the coated rotors, they can be resurfaced. So they recommend the four rotors should be resurfaced and the pads smoothed out. Price = +$400.

This is totally nuts. Does it really cost over $400 to resurface four brake rotors? I have never ever recalled my other vehicles costing so much, even years ago.

Is this a job that Midas or some independent mechanic can handle? This whole thing has been very upsetting, having one dealer tell me the front brakes were shot, while the second says they are holding up ok. What else have they been selling me? (Or not telling me about my battery....)

I thought it was not possible to resurface these special coated rotors anyway? But after years does the coating burn off on its own just from use? So resurfacing wont harm them?

Ughhhhhhh. Any advice would be appreciated.
 

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How many miles are on your Volt? Have you noticed any weird braking behavior? Sounds like the 'stealership' is trying to take you for a ride with unnecessary services. Unless your brake pads are less than 2/32nds of an inch or you have been experiencing weird braking behavior, they probably don't need replacing. Especially on a Volt, which should be using the brakes a lot less than a conventional vehicle due to regenerative brakes.
 

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Wow, who to believe? How many miles do you have on your Volt if I may ask?
 

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Fortunately we don't have much collective experience with brake issues on the Volt but that means that, unfortunately, I'm not sure how much Volt-specific help you'll get here. No idea how you drive or how many miles you have on your car, but after 3+ years I'm not seeing any measurable wear anywhere. Then again I'm still doing OK with the first set of tires so perhaps it's a road/driving combination.

I do think $400 is steep. I'd think you could get it done for $100 at an independent place. I wouldn't take it to a chain repair place. Those places specialize in conjuring up expensive repairs.
 

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My Volt had 35,000 miles on it and it was making mad screeching sound when I pulled in or out of my parking space. I took it to the dealer and after much efforts got them to fix the issue under the bumper to bumper warranty.

First, they blamed the brake pads, saying it could be worn. They wanted to charge me an inspection fee just looking at it. Well it wasn't, in fact, it was virtually brand new still since I brake very gently using regen most of the time. So then they blame the issue on the new brake pads saying it was replaced by a third party- well it wasn't, it was factory stock.

Eventually, they ran out of excuses, and after getting the Volt advisor on the phone, they relented and agreed that my rotors were to blame. They resurfaced it and the noise was gone. They said the rotors were "glazed" - which caused the noise. I am not sure what that means but I am happy with the result. So most definitely you could resurface the Volt rotors. If it is proven that the Volt rotors could be resurfaced, I would rather go to an independent shop to get them done give those prices you mentioned.
 

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Brake Disc Refinishing

Special Tools
• CH-41013 Disc Resurfacing Kit
• CH-42450-A Wheel Hub Resurfacing Kit
For equivalent regional tools, refer to Special Tools .
Warning: Refer to Brake Dust Warning in the Preface section.
Note:
The disc brake discs do not require refinishing as part of routine brake system service. New disc brake discs do not require refinishing.
Do not refinish disc brake discs in an attempt to correct the following conditions:
-- Brake system noise - squeal, growl, groan
-- Uneven and/or premature disc brake pad wear
-- Superficial or cosmetic corrosion/rust of the disc brake disc friction surface -- Scoring of the disc brake disc friction surface less than the maximum allowable specification
• Before refinishing a brake disc, the disc MUST first be checked for adequate thickness to allow the disc to be refinished and remain above the minimum allowable thickness after refinish specification. Refer to Brake Disc Thickness Measurement .
Disc brake discs should only be refinished if they have adequate thickness to be refinished and if one or more of the following conditions exist:
-- Thickness variation in excess of the maximum allowable specification
-- Excessive corrosion/rust and/or pitting
-- Cracks and/or heat spots
-- Excessive blueing discolouration
-- Scoring of the disc brake disc surface in excess of the maximum allowable specification
• Disc brake discs may need to be refinished as part of the process for correcting brake disc assembled lateral runout (LRO) that exceeds the maximum allowable specification.
Note: If the vehicle is equipped with cross-drilled discs, use a lathe with positive rake tooling. This setup requires less cutting pressure, which will result in less vibration, and a better surface finish. Also, use a vibration dampener when cutting. Otherwise, refinish according to the following instructions.
Note: Whenever the brake disc has been separated from the hub/axle flange, clean any rust or contaminants from the hub/axle flange and the brake disc mating surfaces. Failure to do this may result in increased assembled lateral runout (LRO) of the brake disc, which could lead to brake pulsation.
1. Using the CH-42450-A Wheel Hub Resurfacing Kit , thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.
2. Using the CH-41013 Disc Resurfacing Kit , thoroughly clean any rust or corrosion from the mating surface and mounting surface of the brake disc.
3. Inspect the mating surfaces of the hub/axle flange and the disc to ensure that there are no foreign particles or debris remaining.
4. Mount the brake disc to the brake lathe according to the lathe manufacturer's instructions, ensuring that all mounting attachments and adapters are clean and free of debris.
5. Ensure that any vibration dampening attachments are securely in place.
6. With the brake lathe running, slowly bring in the cutting tools until they just contact the brake disc friction surfaces.
7. Observe the witness mark on the brake disc. If the witness mark extends approximately three-quarters or more of the way around the brake disc friction surface on each side, the brake disc is properly mounted to the lathe.
8. If the witness mark does not extend three-quarters or more of the way around the brake disc, re-mount the disc to the lathe.
9. Following the brake lathe manufacturer's instructions, refinish the brake disc.
10. After each successive cut, inspect the brake disc thickness. Refer to Brake Disc Thickness Measurement.
11. If at any time the brake disc exceeds the minimum allowable thickness after refinish specification, the brake disc must be replaced.
12. After refinishing the brake disc, use the following procedure in order to obtain the desired non-directional finish:
12.1. Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish.
12.2. Using moderate pressure, apply the non-directional finish:
• If the lathe is equipped with a non-directional finishing tool, apply the finish with 120-grit aluminium oxide sandpaper.
• If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150-grit aluminium oxide sandpaper.
12.3. After applying a non-directional finish, clean each friction surface of the brake disc with methylated spirit, or an equivalent approved brake cleaner and wipe each friction surface using a clean workshop towel to remove metal particles remaining from machining. Repeat the cleaning process if necessary to remove all metal particles.
13. Remove the brake disc from the brake lathe.
14. Measure the assembled LRO of the brake disc to ensure optimum performance of the disc brakes. Refer to Brake Disc Assembled Lateral Runout Measurement.
15. If the brake disc assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to Brake Disc Assembled Lateral Runout Correction.



FWIW: Although there is a refinishing procedure for the Volt, I would try to get these replaced rather than refinished if you happen to still be under warranty...
 

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GM has reduced the weight of the rotors. Almost all are now throwaway units. They have no spare materials to resurface. They are built at the minimum thickness from the manufacturer. They also stated that groves that were .060in deep or less were acceptable. I f the pads are not worn out, then dirt, small rocks,etc... somehow got under the pads. As far as brake noises, I would remove and inspect the pads for debris, clean them and re-install them. They have a rust resistant coating(sometimes zincs) and a surface hardening process applied. I would ask them to kindly leave the brakes alone!
 

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Discussion Starter #9 (Edited)
Brake Disc Refinishing

Special Tools
• CH-41013 Disc Resurfacing Kit
• CH-42450-A Wheel Hub Resurfacing Kit
For equivalent regional tools, refer to Special Tools .
Warning: Refer to Brake Dust Warning in the Preface section.
Note:
[...]

FWIW: Although there is a refinishing procedure for the Volt, I would try to get these replaced rather than refinished if you happen to still be under warranty...




Wow this is intense! Thank you for the info!!! I guess what applies would be the sections regarding doing resurfacing for either excessive rust, scoring, or pitting. He mentioned something about scoring (looks like Saturn rings to me). So the question is how exactly do you determine excessive scoring, rust or pitting.

Second, no, I have had no problems with the brakes. They seem to stop fine and do not squeak, pulsate, etc. They are far better than the brakes on my old Sonata which always warped within months of replacing the discs, like clockwork.

The Volt now has 97,000 miles (bought it used a few months ago, was a GE fleet vehicle....)

I may take it to another dealer and then also an independent, just for an inspection. It seems like unless the scoring or rust exceeds the GM manual requirements above, then there is no reason to do anything. If the pads were needing to be replaced, then yes I would seriously consider resurfacing them, but if they are still good, and the pads have 'bedded' to the rotors, why resurface? Are there any good reasons to do so?
 

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Sorry to hear about your issue. I drove my 2012 Volt for three years and about 32,000 miles with only minimal wear on the brakes. I think they still had 75% wear left when I had the last inspection a few weeks ago. But I do drive in low most of the time. $600 for a 4 wheel brake job does sound a bit steep to me. You might want to consult with another dealership or mechanic.
 

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Discussion Starter #11
If I have them disassemble the brakes to clean off or sand down the pads, will that harm the stopping distances because the pads would no longer be mated or bedded to the rotor surfaces, including any grooves, etc? Or would the grooves eventually wear down and everything would be fine. I imagine a vinyl record surface....
GM has reduced the weight of the rotors. Almost all are now throwaway units. They have no spare materials to resurface. They are built at the minimum thickness from the manufacturer. They also stated that groves that were .060in deep or less were acceptable. I f the pads are not worn out, then dirt, small rocks,etc... somehow got under the pads. As far as brake noises, I would remove and inspect the pads for debris, clean them and re-install them. They have a rust resistant coating(sometimes zincs) and a surface hardening process applied. I would ask them to kindly leave the brakes alone!
 

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brake jobs are high profit jobs by many shops: they overcharge and it is an easy job.

From tirerack I can buy brand new rotors (set of 4) for $266. $146 for the front and $120 for the rear, plus another $130 for brake pads, or $396 + SH + install labor for all brakes and rotors to be replaced with new parts. I would say $600 from a shop would be reasonable installed (for new rotors AND pads). There is less than 1 hour labor to install all of those, they are simple job (I would assume Volt is standard for pad/rotor replacement).

I am guessing it is just the rotor/pads glazing causing them to squeal (if the rotors are smooth and pads have plenty of material left). You can try sand paper, but when I have done that it tends not to last very long. Better to replace pads with something different and that doesn't squeal. To properly sand you probably have to take the pads and rotors off and work at them for a while. When I sanded mine in an older BMW I had it worked for a day or two then they went right back to squealing. I changed the pads with something less prone to squealing. Might be cheaper just to use new parts rather than turning rotors and sanding pads if you are paying for the service to be done, depending on labor rate.

I would also confirm that your brake pads and rotors are actually worn and not just the shop telling you they are. The Volt has pretty open wheels, so you should be able to see the pads through the wheel opening, and their should be a fairly large gap between the backing plate and the rotor. I will see if I can post a picture later how to check.

I think the Volts brake "problems" stem from lack of use. They glaze over when you don't use them, you need to use them hard occasionally to make sure the surfaces are free of corrosion and such. Maybe try a panic stop from 60 in safe place (assuming your pads are safe thickness)
 

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OK, ..

Chevy Dealer A told me about two weeks ago that I need to replace the Volt's front brake pads because they were worn down, plus the rotors. Said the rotors cant be turned/resurfaced... because there's a special coating on the rotors. Price = +$600

Now, the car is at Chevy Dealer B up in the burbs getting the transmission fluid and coolant flushed and new OEM tires. They tell me that all four brakes and the pads are fine, with about 50% life or about two years left on them. However the rotors are worn/scored, but thick enough to be resurfaced. The Volt mechanic said even with the coated rotors, they can be resurfaced. So they recommend the four rotors should be resurfaced and the pads smoothed out. Price = +$400.

...Any advice would be appreciated.
I think the larger question is why your brake rotor/pads are wearing badly, unless you are braking pretty hard, most braking effort is regenerative. The system uses as much regeneration as it can to meet your brake pedal request before squeezing the pads.

The rotors do have a heat treated surface which GM calls FCN, it is intended to reduce rust, and certainly makes the rotors more expensive. I don't know if it affects brake performance or not, though I doubt it.

The brakes on my Passat, if I have the dealer do the work, cost $500 per axle. Factory parts, dealer rates, you know the routine. If that sound painful, try getting your Mercedes brakes replaced at the dealer.
I'm sure that you can have midas or any local shop you like redo the brakes, I just looked on Autozone, the front rotors are $57, the rear rotors are $47 ea. you know the routine, these are the right dimensions and made in wherever they are least expensive,and sure they will rust up, but don't everyone elses brakes rust too?
 

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Starting in 2011 the Volt was one of the first cars to utilize rotors with a new special hardening treatment called Ferritic Nitro-Carburizing (FNC), however it doesn't really affect brake service or repair all that much. It does create a harder braking surface (ideal for ceramic pads) and reduces rust formation on the rotor surfaces in wet or winter conditions.

As for basic brake maintenance (ie worn out pads after ~100,000 miles) it is simply suggested the pads be replaced and the caliper mounting verified and caliper mounting bolts/seals inspected, and if necessary sliders cleaned and lubricated as well as other critical caliper contact points.
Then during this basic brake service, the rotors are to be measured for minimum thickness (0.913") and thickness variation (max 0.001" over 4 evenly spaced spots), assembled lateral runout (0.002" max), and surface groove width/depth (max 0.060")


If ANY exceed specifications the Volt's rotors CAN USUALLY be resurfaced providing there is still sufficient material remaining. A new Volt rotor is 1.025" thick and can be safely machined down to 0.913" which still leaves sufficient material to permit a second friction surface life cycle. So if they can't remove any deep grooves without surpassing that dimension, the rotor should be replaced (BOTH if front axle and ALL 4 if the faulty rotor is in the rear- to prevent braking bias instability )

So if a service facility wishes to machine or replace the rotors, you may wish to question WHICH of these inspections exceeded specifications. A few concentric grooves less than 0.060" deep will not significantly affect brake performance. New pads will work themselves in after a couple of moderately hard stops (part of a burnish procedure usually performed by the technician immediately after brake job completion)

Based on what I am hearing in this particular case, (no braking performance concerns or noises, 100K pad wear, a few grooves in rotors, the suggested service would be simple pad replacement/external caliper service leaving the rotors untouched UNLESS there's something that measures out of specification.

Keep in mind shops often suggest rotor replacement (or even caliper overhaul) during brake service simply to create "as-new" friction surfaces for the brakes AND to reduce the likelihood of any "comebacks" for additional complaints/concerns (vibrations, pulsations, noises, performance) after a recent brake job.

There's no disputing putting on all-new pads, calipers, and rotors on all 4 corners will completely renew the braking system.
But that prospect is often unnecessary AND expensive.

HTH
WOT

PS> After re-reading some of the OPs follow-up posts. NO ATTEMPT should be made to sand, file, or otherwise resurface the brake PADS themselves. Also, if you check online for FACTORY front brake pads (all I would ever use or recommend) they are over $100 per set MSRP, and the front rotors a little over $100 each, then most shops will charge around 1-1.5hrs labor per axle (including all critical measurements) so...
 

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After inspection, I would just remount the pads. In the event there are a few spots from debris removal, these will be polished in within a few hundred miles. You probably won't notice any difference. The Volt's regen system does a lot of the braking during light deceleration stops. I would expect 100,000++ brake pad life. If you don't have pulsing during a stop, the runout deviation is within normal limits.
 

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Discussion Starter #16
Thanks to all of the extremely helpful posts here! I will definitely at least consider doing the service to the brake calipers, getting them lubed or whatnot, as part of the brake service.

One thing -- when I go to the dealer (or the next dealer) and ask them about the brakes, what GM Policy or protocol or whatnot should I reference? i.e. "Were the grooves in the Volt's rotors deeper than x-mm per GM service manual #12345. No? Then why do you recommend replacing or resurfacing them if GM says they don't technically need to be resurfaced......"
 

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My 12 Volt has 25K miles.

I ALWAYS drive in L.

IMO the brakes will last the life of the car. But again I don't drive on winter roads with salt coatings.
 

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I agree I think the brakes will last over 100k miles. I've got a little over 5,000 miles and the car hasn't been washed since new. The front wheels are still the normal wheel color vs. brake pad black. I've never seen so little brake dust in my life.

I ALWAYS drive in L.
If you always drive in L, seems like you are missing out on a lot of coasting. Even on the flat in L I've seen that it uses more power to maintain speed than when letting off the accelerator and coasting for a bit. Do you find that isn't the case? I'm just curious about your experience.
 

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2011 here, 44,000 miles. Brakes are nearly new in terms of spec. Had it at a shop for a tire rotation and they did a look at the brakes and said they were in great shape. Only real wear is when my daughter drives and she does a little too much braking right at stop signs and hasn't learned a smooth technique yet.
 

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One thing -- when I go to the dealer (or the next dealer) and ask them about the brakes, what GM Policy or protocol or whatnot should I reference? i.e. "Were the grooves in the Volt's rotors deeper than x-mm per GM service manual #12345. No? Then why do you recommend replacing or resurfacing them if GM says they don't technically need to be resurfaced......"
WOT gave you the specs and advice you need to know. Throwing the manual at the service advisor usually isn't helpful. Try not to turn it into a battle - just ask the right questions and have the specs he gave you written down.

I know, it's hard to do when you feel like you're dealing with a liar.
 
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