Coated Rotors vs uncoated.

I personally prefer coated rotors. A couple of times I couldn’t source them and used VHT brand paint on the inside and out of the rotor hat, and it’s held up just as well here in the south, at least. The Genesis is a nice car - I’d go the extra step to buy or spray.

if you buy, the pads scrape off the excess material in about 10 feet, and the first ease of the brake pedal halts the car. After that, they are ready to go.

what pads are you considering? I’ve tried a bunch of different brands and have very happily settled on the element3 pads, including on our Lexus gs350, which is similar to your Genesis.
Im looking to buy akebono ceramic pads. ive heard great things about them!
 
I wouldn't worry that much about what I see (the rotor face
and hub), I'd worry more about what I don't see - rust within
the rotor's ventilation channels. When the vanes got stuffed full
with rust the rotors aren't vented any longer and as a conse-
quence both rotor and - much more important - the pads will
inevitably get hotter after enduring or repeated braking which
could result in fading or even boiling brake fluid as hotter pads
will led to hotter calipers. Remember it's the rotor with its huge
surface that cools the pads.
So the question is, what does 'coated' actually mean? If there's
just some paint on the rotor face and the hub, this is a purely
cosmetical measure. However if the entire brake disc assembly
is zink plated it would provide much more of a benefit. It still
won't protect from rusting forever, but it'll likely last longer in
salty environments.
.
 
I've had rotors rust from the inside out, usually on lightly driven vehicles in humid conditions, and once any salt gets in (not a SoCal problem) it's basically impossible to get out. You don't want a rotor coming apart in hard braking, VERY BAD THINGS HAPPEN!! Now that virtually all rotors are made in China, seems like casting quality & thickness are a huge variable. The xB actually rusted it's drilled & slotted eBay zinc dichromate rotors, put the Element3 coated ones on-awesome so far!
 
I wouldn't worry that much about what I see (the rotor face
and hub), I'd worry more about what I don't see - rust within
the rotor's ventilation channels. When the vanes got stuffed full
with rust the rotors aren't vented any longer and as a conse-
quence both rotor and - much more important - the pads will
inevitably get hotter after enduring or repeated braking which
could result in fading or even boiling brake fluid as hotter pads
will led to hotter calipers. Remember it's the rotor with its huge
surface that cools the pads.
So the question is, what does 'coated' actually mean? If there's
just some paint on the rotor face and the hub, this is a purely
cosmetical measure. However if the entire brake disc assembly
is zink plated it would provide much more of a benefit. It still
won't protect from rusting forever, but it'll likely last longer in
salty environments.
.
Seems like rusty ones warp more easily too, either from vane rust or overheating. They're an often overlooked safety annoyance that can become a disaster. Like having a beat up Envoy make a 90 degree left turn in front of me, on I-75, at ~60 MPH. ON TWO WHEELS! Shearing the front end of a Touareg clean off! Miracle no one was killed. Including me.
 
I wouldn't worry that much about what I see (the rotor face
and hub), I'd worry more about what I don't see - rust within
the rotor's ventilation channels. When the vanes got stuffed full
with rust the rotors aren't vented any longer and as a conse-
quence both rotor and - much more important - the pads will
inevitably get hotter after enduring or repeated braking which
could result in fading or even boiling brake fluid as hotter pads
will led to hotter calipers. Remember it's the rotor with its huge
surface that cools the pads.
So the question is, what does 'coated' actually mean? If there's
just some paint on the rotor face and the hub, this is a purely
cosmetical measure. However if the entire brake disc assembly
is zink plated it would provide much more of a benefit. It still
won't protect from rusting forever, but it'll likely last longer in
salty environments.
.
does anyone actually coat the insides? I’m not sure I’ve come across it?
 
Im looking to buy akebono ceramic pads. ive heard great things about them!
The blue box ones are okay, generally quiet, nothing special.

The yellow box ones are pretty good, but can be noisy, especially when cold.

Neither are truly worth the money over OE.
 
Old thread and it'll be obvious (I guess) that I don't know what I am talking about - but you guys are saying it's OK (and worth it) to PAINT the friction surfaces of a brake rotor? Wow I would have NEVER thought that was OK - but then even if it is OK, the paint would wear off instantly or in very short order, meaning a mostly useless effort. Plus - I don't think I have ever seen a painted rotor (calipers yes of course).
 
Old thread and it'll be obvious (I guess) that I don't know what I am talking about - but you guys are saying it's OK (and worth it) to PAINT the friction surfaces of a brake rotor? Wow I would have NEVER thought that was OK - but then even if it is OK, the paint would wear off instantly or in very short order, meaning a mostly useless effort. Plus - I don't think I have ever seen a painted rotor (calipers yes of course).
Where did you see the recommendation to paint the friction surfaces?
 
This is a great question and needs to be determined.

Coated rotors are great, however, if pads are not aggressive enough to remove the initial layer, it can be more problematic.

Non-coated rotors will rust prematurely.

Painted rotors probably the best of both worlds IMO.
 
This is a great question and needs to be determined.

Coated rotors are great, however, if pads are not aggressive enough to remove the initial layer, it can be more problematic.

Non-coated rotors will rust prematurely.

Painted rotors probably the best of both worlds IMO.
I'd think a proper bedding after installation would remove any coating, regardless? I always do ten relatively hard stops 40-5mph after every brake job then drive several miles minimum to allow cooling. I can't say I've ever visually observed if any coating remained, but if I felt the brakes weren't grabbing well I would look I suppose.....

And I agree coated rotors are great even in places with little rust. But if I find non-coated on closeout or Warehouse Deals I'll grab them just the same.
 
I'd think a proper bedding after installation would remove any coating, regardless? I always do ten relatively hard stops 40-5mph after every brake job then drive several miles minimum to allow cooling. I can't say I've ever visually observed if any coating remained, but if I felt the brakes weren't grabbing well I would look I suppose.....

And I agree coated rotors are great even in places with little rust. But if I find non-coated on closeout or Warehouse Deals I'll grab them just the same.
Well, it wasn't the case with Akebono Pro Acts.
 
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If in S. Cal, I'd just buy non-coated and save the cash to put towards better rotors or pads. Even up in the salt belt I don't see the coated lasting a whole lot longer even. I've used both and experienced no real difference. Just my 2c.
 
Got a full brake job coming up on my genesis, and Ive come across between buying coated rotors or non coated ones. Are they worth the $45 upgrade to have them be coated as opposed to just buying the uncoated rotor set? I live in southern California, no harsh winters or salt roads here. Should I save myself the money and just stick with the oem uncoated ones, or is it worth having the coated ones because they are graded as "lasting longer"
Go with coated. If you want to extend the life you can cryo treat the rotors as well
 
Mercedes factory rotors, and rotors from companies like Zimmerman, come coated, including the friction surfaces, with what appears to be a layer of zinc primer. I’d be OK with zinc primer on friction surfaces, since they do it, but not an actual paint. I would be concerned about the effect of the paint solids getting ground into the surface of the pads.
 
I mentioned earlier in this thread about Bosch Rotors being painted silver and it did seem to me to be ordinary silver paint rather than primer. After I fitted them the braking was so bad I thought it dangerous and took the wheels off again to abrade the majority of the paint off by hand. This is years ago now and I forget what pads I used but I'm thinking I must have made a poor choice and that pads for use with coated rotors should have an initial very abrasive layer to take the coating of quickly. Once the paint was all gone the brakes were fine for many years and as good as the OEM discs and pads.
 
I wouldn't worry that much about what I see (the rotor face
and hub), I'd worry more about what I don't see - rust within
the rotor's ventilation channels. When the vanes got stuffed full
with rust the rotors aren't vented any longer and as a conse-
quence both rotor and - much more important - the pads will
inevitably get hotter after enduring or repeated braking which
could result in fading or even boiling brake fluid as hotter pads
will led to hotter calipers. Remember it's the rotor with its huge
surface that cools the pads.

.
When I was younger and had more free time, one of my annual procedures was to remove the wheels and take a gun cleaning rod and brush of appropriate size and run it through the drilled holes (if any), then through the vanes. I was surprised at the amount of rust and crud that would come out...I would sometimes do it at a shorter interval, still a surprising amount of crud. These were Brembo brand rotors.

None of my cars have drilled rotors, with the exception of the Ferrari, and these are carbon ceramic, so don't bother.
But I gave up cleaning the vanes...too lazy. :)
 
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