Need new rotors - OEM vs AcDelco Severe Duty

Canadian GM Guy · May 9, 2020

Hi guys, feel free to move this thread if it's in the wrong topic. I need rotors for my 2017 Silverado, my current rotors have 107,000km on them and are starting to pulsate. As the title states, should I go with the OEM ones with their FNC (feretic nitrocarburizing) process which I must admit are incredibly durable to have lasted me over 100,000km. Or the specialty units which supposedly are made by raybestos and have a higher carbon content in the metal to absorb and dissipate heat but no FNC corrosion resistance.

I now live in a mountainous area that's not by the ocean and has pretty minimal rain fall, however in the winter time calcium chloride is used prior to snowfalls. Winter is fairly short lived and snow is minimal now where I live unless I drive the mountain pass. I drive it like I stole it and use my brakes hard.

Advice???

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btj_z71 · May 9, 2020

1 hour ago, Canadian GM Guy said:

Hi guys, feel free to move this thread if it's in the wrong topic. I need rotors for my 2017 Silverado, my current rotors have 107,000km on them and are starting to pulsate. As the title states, should I go with the OEM ones with their FNC (feretic nitrocarburizing) process which I must admit are incredibly durable to have lasted me over 100,000km. Or the specialty units which supposedly are made by raybestos and have a higher carbon content in the metal to absorb and dissipate heat but no FNC corrosion resistance.

I now live in a mountainous area that's not by the ocean and has pretty minimal rain fall, however in the winter time calcium chloride is used prior to snowfalls. Winter is fairly short lived and snow is minimal now where I live unless I drive the mountain pass. I drive it like I stole it and use my brakes hard.

Advice???

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I recommend you have them turned by a brake shop before replacing. Turning a rotor is the process of smoothing the contact area. That will take care of the vibration.

Canadian GM Guy · May 9, 2020

I recommend you have them turned by a brake shop before replacing. Turning a rotor is the process of smoothing the contact area. That will take care of the vibration.

Can't, they're below GM specified minimum thickness.

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dieselfan1 · May 9, 2020

12 hours ago, btj_z71 said:

I recommend you have them turned by a brake shop before replacing. Turning a rotor is the process of smoothing the contact area. That will take care of the vibration.

Nobody does that any more do they?

Rotors are fairly cheap .

rav3 · May 9, 2020

7 minutes ago, dieselfan1 said:

Nobody does that any more do they?

Rotors are fairly cheap .

Yes, some people (owners) do & many Auto shop still do turning. There's a newer process where they turn you rotors while they're still on the car/truck but I'm not sure what that costs. I think regular turning is about $15/$20 per rotor. Turning is about the same price as new If you buy the cheap/less expensive rotors (usually from China) @$20-$30 each. If you where to but AC Delco, which I think is the same as GM's OEM, they run about $53-$56/each from what I've seen. To me, it's an individuals/personal choice on how they like to spend money on their trucks. I may get flamed on this one, but in years past, I have never had any problem running rotors beyond the min. thickness on BMW's or Chey trucks. I think it's more of a liability issue with the Mfg. They don't want to get sued if someone can put blame on them for NOT recommending new rotors & you have an accident. They have to put limits somewhere. With that said, all my driving had been more of commuter driving than hauling a heavy trailer. If that were the case, I'd for sure replace rotors & pads.

To the original question about which rotors to buy (should I go with the OEM ones with their FNC (feretic nitrocarburizing) , here's what I found on that.

"Ferritic nitrocarburized surface treatment of cast iron brake rotors providing oxidation resistance, good braking performance and absence of distortion. Machined brake rotors are pre-heated, then immersed into a high temperature molten nitrocarburizing salt bath for a first predetermined dwell time. After removing the brake rotors from the nitrocarburizing salt bath, the brake rotors are directly immersed into an oxidizing salt bath at a lower temperature than the nitrocarburizing salt bath so that the brake rotors are thermally quenched. After a predetermined second dwell time in the oxidizing salt bath, the brake rotors are removed therefrom and further cooled to room temperature, either by water application thermal quenching or slow cooling in air. A fixture provides stable holding the brake rotors with a minimum of contact during placement in the salt baths."

I retired from a Tool & Mold shop after 40 years. We had our own heat treating department that we did "Nitriding" which is technically the same as described above. This actually puts a thin hardened case on the surface of steel, so I would assume it does the same on these cast Iron rotors. I'm not sure how much rust prevention it does.

New AC Delco rotors on RockAuto,com call out that they are "ACDelco Advantage Coated Brake Rotors provide reliable braking power. Their robotic-applied, baked-on coating helps prevent brake pulsation, helps prevent the rotor from seizing to the hub, and provides excellent rust prevention against harsh environmental elements such as rain, snow, and corrosive road sprays. "

I'd probably go with some this like this myself. I know ALL newer BMW's come now with a Coating that helps prevent rust. The rotors I had on my last truck ('96 Ext cab Z71) they rotors would rust terribly. That's got to be NOT GOOD.

Good luck with your choice.

rav3 · May 9, 2020

Here's a good article on the "GM doubles brake-rotor life with Ferritic Nitro-Carburizing "

https://www.torquenews.com/119/gm-doubles-brake-rotor-life-ferritic-nitro-carburizing

Canadian GM Guy · May 12, 2020

I'm very torn on the one hand you have the OE ones that are FNC and "durable" and on the other you have the severe duty rotors that are supposed to be better for just that.... severe use.

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Lsgun1 · May 12, 2020

If you are happy with the OEM why change?

diyer2 · May 12, 2020

I drive it like I stole it and use my brakes hard.

Heat dissipation maybe a better choice.

:)

truckguy82 · May 12, 2020

I’m a big fan of oem

I took my truck to the dealer to replace the pads and rotors, stupid me assumed they were using oem. Got some other AC delco brakes. When I came back and confronted them, they said....”they come off the same assembly line”

the hub was rusted to ****** in a month, and they squeel in reverse.

best of all, it was the first time in my life I decided, “I have enough money, let me pay someone to do my brakes for me.”

edit:just realized that was a pretty off topic rant

Edited May 12, 2020 by truckguy82

Canadian GM Guy · May 15, 2020

Thanks for the input everyone.

Here are the benefits of each as I see them...

OEM:
FNC coating (anti corrosive as hell but that's about it)

AcDelco Severe Duty:
Maybe not be as anti corrosive but should handle heat more efficiently and warp less because of the metallurgy

Does anyone have any other suggestions I should be looking at?

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Ozer · May 15, 2020

A lot of people also use PowerStop z36 kit for trucks, including me. I have no complaints and you can find it in many places online.

I got mine from RockAuto. https://www.rockauto.com/en/catalog/gmc,2014,sierra+1500,5.3l+v8,3294374,brake+&+wheel+hub,rotor+&+brake+pad+kit,13824

They have the AC delco one you speak as well, they both should be good for what you want.

swathdiver · May 15, 2020

Go GM OE, truck still stops great right? ACDelco Advantage is el cheapo stuff. That's what I did, no regrets.

rav3 · May 15, 2020

This does bring up an interesting question 'for me' anyway. Who does make OE Rotors for GM? Here's what I found when I did a search.

GM OE Brake Rotor

Now "click" on the link for "Buy Parts". Then when you get to that page..'Click' on "Find online"

It will bring up (5) online sources. Did you guess right?..https://www.acdelco.com/shop/brakes#!?productLines=17

kickass audio · May 15, 2020

I just replaced my front brakes since the rotors had a good lip on the outside edge of the inner side of the rotor. The pads were less than a quarter of life left and I knew the dealer would fail my inspection for it, hell they put my rears as having less than half their life on them when I just replaced the pads only a year ago, there is no way that burned through that fast.

Anyway, I went with these rotors https://www.amazon.com/gp/product/B01IU5HYJQ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 and these pads https://www.amazon.com/gp/product/B01E6IWZW2/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 and the stopping power is a whole hell of a lot different now. It stopped fine before but my brakes are so much more responsive now and I have never had that experience in the past with any brake service I have performed. I had to replace one of the rubber slide pin boots as it had a tiny hole in it and let water get in and rust the pin a bit but I just put the pin on the wire wheel and it is brand new again and the bore was perfect. I also finally bought a brake caliper file https://www.amazon.com/gp/product/B00XMRE040/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1 and use it to clean all of the surface rust chunks off of the mounting tabs where the pads sit in the bracket and greased up both sides with permatex ceramic lubricant.