[Spike00513]

Time for brakes. My pads and rotors are worn thin.

I'm thinking of getting Centric C-Tek standard ($15/ea) rotors new from RockAuto.
Is that OK? Or do I have to get more expensive Ate/Zimmerman/Brembo/etc.?
if so, why?

What pads should I get, and why?

Thank you

 

[atmsmshr]

I use Akebono Euro pads on all 5 of our vehicles. Primarily because they are dustless and have good stopping power. They are a bit more expensive.

 

[Spike00513]

I use Akebono Euro pads on all 5 of our vehicles. Primarily because they are dustless and have good stopping power. They are a bit more expensive.

I've heard this about them, but I don't mind taking a minute or two once a year to do a quick wipe-down of the wheels, in the case of semi-metallic dust, especially if it's significantly cheaper. I figure that so long as the wheels start out cleaned, sealed, and waxed, the brake dust build-up won't harm them. If it does, no big deal, they're old cheap wheels and silver spray paint is cheap.

What rotors do you use?

 

[hamada128]

I used the Zimmerman mad in Germany rotors with the TEXTAR pads and everything works as it should. But I might consider going to Akebono pads next time just as a try and see the difference.
I would recommend to stick with a good quality rotors though.

 

[Kajtek1]

Are you sure you need new rotors.
Our rotors at 260,000 miles had about 50% of usable thickens on them. I had to grind off the lips, but that was about it.
One more vote for Akebono. Beside low dust, they seem to be lifetime pads and I sold the car, but my estimate is that with our driving they should deliver 300,000 miles of service.

 

[Spike00513]

I used the Zimmerman mad in Germany rotors with the TEXTAR pads and everything works as it should. But I might consider going to Akebono pads next time just as a try and see the difference.
I would recommend to stick with a good quality rotors though.

How do you tell if a rotor is good quality or not?

Are you sure you need new rotors.
Our rotors at 260,000 miles had about 50% of usable thickens on them. I had to grind off the lips, but that was about it.
One more vote for Akebono. Beside low dust, they seem to be lifetime pads and I sold the car, but my estimate is that with our driving they should deliver 300,000 miles of service.

I took off the wheels and measured the rotor thickness, with measuring calipers. However, I did not use accurate electronic calipers. I only used the cheap plastic ones. The rotor minimum thickness specification is written on the rotors. According to my measurements, the rotors have reached that minimum thickness. This leads me to believe they're in need of replacement. The pads are also worn out. I believe the car is on original rotors, but 2nd set of pads. It has 140k mi.

 

[e-420]

another vote for akebono's. IMHO MB (and BMW) must collect brake dust from europe and put it in the pads for the U.S. A 3 mile trip to the store and there was black dust on the wheels with stock pads. not visible, but on your fingers if you wiped the wheel.

Akebono's solved that problem and IMHO the difference in stopping power, brake feel, etc. is so slight that most cases a blind test someone couldn't tell which pad they had. And they do seem to last longer than stock pads.

As for rotors, if you need them just go with stock MB rotors. reasonably priced.

 

[Kajtek1]

Akebonos can STOP the car.
After driving W210s for about 10 years I never had a chance to see BAS working.
Than in last year I gave it twice "chance to show" it and it did work.

 

[hamada128]

How do you tell if a rotor is good quality or not?

I mean To buy OE brands rotors such as ATE, Zimmerman, etc and not get the unknown brands that the Autoparts chain stores have over the shelves.

 

[Kajtek1]

Rotors are cast iron and IMHO there is not much you can screw on machining.
I've been buying cheaper rotors from reputable suppliers and never had a problem.
Than lately fellow member come with his MB having problem with new brakes that 3 shops gave 3 different diagnosis.
We took the time to inspect everything and turn out that MB rotors had material with different density in couple of points. That was invisible on new rotors, but with some wear different density made slight pulsation.

 

[hamada128]

Kaj, when you say cheaper rotors that's how much?
I bought the Zimmerman for the W210 for $75 and $68 for the W201.

 

[Kajtek1]

Last time I bought rotors was like 5 years ago for Audi.
Found Canadian ebay dealer with huge volume and I remember set of rotors and pads was slightly above $100

 

[hamada128]

Last time I bought rotors was like 5 years ago for Audi.
Found Canadian ebay dealer with huge volume and I remember set of rotors and pads was slightly above $100

Almost what I paid for the Zimmerman with the textar pads.

 

[MBGraham]

Almost what I paid for the Zimmerman with the textar pads.

$100 for complete set? Or per wheel? At AA, complete set would be about about $350, wouldn't it?

A year or more ago, I installed rear coated Zimmerman rotors and Pagid pads (supposedly use OE compound). They squealed. May be to do with lack of shims and type of anti-squeal I used. This year, squeal seems to have gone away - Maybe the rust after storage helped

I like the Zimmerman coating, but it does end up on the pads. I would probably use it again and Textar pads would be a good choice.

Checked my records and found that in 2004 I paid over C$300 for OE front rotors and pads at dealer.

Regarding cheap rotors. They "may" be OK, but CI is not just CI. It depends a lot on casting process and treatment. This article describes it better than I can. At the price it may be worth trying them. So easy to change on W210 anyway.

 

[Kajtek1]

Regarding cheap rotors. They "may" be OK, but CI is not just CI. It depends a lot on casting process and treatment. This article describes it better than I can. At the price it may be worth trying them. So easy to change on W210 anyway.

You are linking sales pitch site, what is not giving you reliable info.
They misuse description of "heat treating" and that look intentional. Cast iron can NOT be heat treated
When metal stabilization in cast iron might make sense, I doubt any manufacturer, beside racing industry is actually doing it on rotors.
I drove Fiats and Skodas that had rotors made the cheapest way possible and had no warped rotors in my life.

 

[MBGraham]

You are linking sales pitch site, what is not giving you reliable info.
They misuse description of "heat treating" and that look intentional. Cast iron can NOT be heat treated

I chose a site with a simple explanation.

For everything you want to know about cast iron and it's use in brake rotors, read the following attachment by SAE (and TRW who also make brake stuff).

Keep going to near end and you will find the sections on heat treating, stress relieving, annealing and other treatments that are used with cast iron rotors.

I somehow doubt those cheap Chinese rotors are made with the same care as German or even domestic rotors.

Here is link:
http://www.sae.org/events/bce/tutorial-ihm.pdf

 

[Kajtek1]

I somehow doubt those cheap Chinese rotors are made with the same care as German or even domestic rotors.

Here is link:
http://www.sae.org/events/bce/tutorial-ihm.pdf

Rotors do have pretty loose tolerances, so high-tech machining does not apply here.
You think German hire high tech machinist for rotor producing? I know that most of those workers are Turkish, Ukrainians, Polish and other immigrants.
Coming to heat treatment, page 88 of the site says
"Stress relieving has no significant effect on
microstructure or mechanical properties."
Page 90 "Many other heat treatments have been considered to
improve specific properties of the gray cast iron, but
the costs and/or the technical disadvantages have
outweighed the benefits."

 

[MBGraham]

Rotors do have pretty loose tolerances, so high-tech machining does not apply here.
You think German hire high tech machinist for rotor producing? I know that most of those workers are Turkish, Ukrainians, Polish and other immigrants.
Coming to heat treatment, page 88 of the site says
"Stress relieving has no significant effect on
microstructure or mechanical properties."
Page 90 "Many other heat treatments have been considered to
improve specific properties of the gray cast iron, but
the costs and/or the technical disadvantages have
outweighed the benefits."

I think the machining is likely automated. You don't think immigrants can do a good job? (By the way, we are ourselves probably both immigrants )

You cheated and cherry picked from the Stress Relieving page Here is whole page:

Stress Relieving Heat-Treatment of
Gray Cast Iron Rotors
• Stress relieving of gray cast iron rotors can be
performed to minimize rotor warpage that can occur
under extreme service conditions.
• Stress relieving of semi-finished rotors is done in
Europe for many rotors designed for high performance
vehicles.
• Stress relieving is typically performed in the
temperature range of 500°C and 650°C for periods up
to 24 hours.
• Stress relieving has no significant effect on
microstructure or mechanical properties.

Regardless of the technicalities of making Cast Iron rotors, I will continue to buy name-brand rotors for our "European High Performance Vehicles"

Zimmerman address the quality issue on their website:
Otto Zimmermann Bremsscheiben GmbH -

I am interested in learning from others who buy the low cost alternatives. I seem to recall someone saying (perhaps on another forum) that they bought very low cost rotors made in Ontario, Canada. We live here, but I don't know who sells those?

 

[Kajtek1]

And again, I believe I drove on non-stress relieved rotors 98% of my life and never had bad experience.
Notice that the "high performance vehicles." is not explained, so we don't even know if W210 rotors fall into the category.
Coming to immigrants, aren't they who made US of A the greatest country in the World?
Their offspring lost the motivation to work hard

 

[Spike00513]

Notice that the "high performance vehicles." is not explained, so we don't even know if W210 rotors fall into the category.

I doubt it. Otherwise the rotors would be bigger, and the rears would be thicker with vanes instead of tiny solid discs.

The "superior metallurgy" Zimmerman test linked above points out that competitor rotors last ~80 brake abuses, whereas it takes ~200 for the Zimmermans to break. I don't see why this matters. I don't slam on the brakes 80 times when I drive. That is something you do only once, maybe if a deer jumps onto the road.