Drlled & Grooved - for the beater?

[artificialist]

Originally Posted By: pzev
Its been the case in the past where Chinese made rotors were of poor quality, butt they have improved over the years. If you look hard enough, you can often find US or Canadian made rotors.
If the issue of rust is important to you, then grab a role of masking tape and some high temp paint. If you prep the rotor before hand, and do a good job, the paint will hold up just as long as any zinc coating...not to mention you have a wide range of colors to choose from

.

I find that many factory Chrysler rotors are made in Canada, but I find that mid-grade Chinese rotors resist warp better than O.E. Chrysler stuff.

Badly made Chinese rotors still exist. I remember once I had to install ridiculously 1 cheap rotor and one nice rotor on the back of a Ford Crown Vic. Within one week, the cheap one warped like crazy, but the nice one was okay.

 

[Astro14]

Originally Posted By: SteveSRT8
I have yet to see any Merc anywhere with slotteds. Did you mean cross drilled?

You're right...I typed that and the next day noticed that they were cross-drilled. Car in question was an E-350 MB with the sport package (thank you Hertz Gold!

) Great car by the way...with great brake pedal feel, even if it was a bit on the touchy side....it also had 245/40 R18 front, 265/35 R18 rear, tires...and a very smooth ride despite the low profile...

If "all cross-drilled rotors crack" as was stated above...why would the OEM install them? I have to believe that this set on the MB will hold up under hard use...Mercedes has taken some hits on reliability...but they are still among the best and braking systems are important on a sports sedan like this.

I think that perhaps "cheap cross-drilled rotors crack" is the more likely case...

Still - to the OP's question: for the beater? I wouldn't bother with the expense...kinda' defeats the purpose of a beater if you go pouring $$$ into it...

 

[PandaBear]

Blank

If you want better performance, spend the money on better pad and big brake kit (reworked OEM parts with blank rotor, OEM caliper, etc from another model, etc) and bigger rims to fit them in.

 

[pzev]

Originally Posted By: Astro14
Originally Posted By: SteveSRT8
I have yet to see any Merc anywhere with slotteds. Did you mean cross drilled?

You're right...I typed that and the next day noticed that they were cross-drilled. Car in question was an E-350 MB with the sport package (thank you Hertz Gold!

) Great car by the way...with great brake pedal feel, even if it was a bit on the touchy side....it also had 245/40 R18 front, 265/35 R18 rear, tires...and a very smooth ride despite the low profile...

If "all cross-drilled rotors crack" as was stated above...why would the OEM install them? I have to believe that this set on the MB will hold up under hard use...Mercedes has taken some hits on reliability...but they are still among the best and braking systems are important on a sports sedan like this.

I think that perhaps "cheap cross-drilled rotors crack" is the more likely case...

Still - to the OP's question: for the beater? I wouldn't bother with the expense...kinda' defeats the purpose of a beater if you go pouring $$$ into it...



There is a perception of "bling" associated with sports cars and luxury sedans, hence why these types of rotors are found on such vehicles. Cast iron cross drilled rotors will crack if abused enough. To compensate for this issue, OEM cross drilled rotors are usually of substantial size and mass, which gives them ample thermal capacity and can resist cracking longer. However, there is still a risk of cracking. Mind you, I'm not talking about catastrophic failure...small spider cracks appear next to the cross drilling, and if the car sees any regular maintenance at all, a tech would easily spot it and replace the rotor. To someone with deep enough pockets to afford such a car, a rotor replacement would be trivial.
That said, less expensive cars typically use much smaller rotors...aftermarket cross drilled variants of these rotors are much more prone to cracking because they lack sufficient size to properly put up with abuse. If its a daily driver, you'll probably be fine...but if you hot rod the car, then you're risking spider cracks developing on the rotor.

Go to a porche forum, and talk to anyone who regularly takes their car to a race track. You'll find that cracked rotors are a whole lot more common then you might think. As I mentioned in an earlier post, carbon-ceramic style rotors seem to resist these issues...at a serious price increase.


And to reply to another poster in this thread, there are MB vehicles with slotted rotors from the factory. My sisters 98 C230 had a spiral slotting pattern on the front rotors. Never seen another rotor like it. We replaced them with blanks when she needed a new set of front brakes, no issues with the change.
Slotting is common on euro vehicles due to the grimy road conditions they have historically put up with. Slotting does indeed aid in evacuating any debris that can accumulate between the rotor and pad, this includes water, slush, snow, dirt, etc. For the same reason MB cars often had headlight washers...to clear the [censored] away.
As mentioned earlier however, there are tradeoffs to these slots.

 

[pzev]

Too late to edit my post. Anyways, regarding the MB slotted rotor...it appears the rotors we replaced on her car were already aftermarket items. Car was used when she bought it, however it was only a couple years old at the time. Odd they would have already replaced the rotors. I searched to find a picture of them, and the only rotor that matches are ATE PremiumOne rotors...and I can't verify that they would have been an OEM item...so I figured I'd add this disclaimer.
Here is a picture of the rotors in question:

 

[Drew2000]

Centric Premium-Black rotors are very good quality at a good price...made in Taiwan. E-coated to resist rust and warp resistant. Much better than the OEM Ford rotors on my Tribute.

 

[Roger1960]

I think a lot depends on how you drive. I worked at a place where one guy had to burn premium gas and he also had brake jobs 3 or 4 times more often than I did and I believe I had a heaver truck then he did.

My ex-wife went 175.000 miles on the original set of brakes on a Ford Taurus. Admittedly this is a small town and most of her driving was open road and cruise control but my experience is that regular old brakes last a [censored] long time if you go easy on them.

Now if you tow a heavy trailer and have a lot of steep downgrades, that might be a different story.