Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 12-30-2009, 09:40 PM
truckinik's Avatar
And I only had one lesson
Join Date: Jan 2007
Location: Clearwater Beach, Florida
Posts: 1,022
Years ago, Rotors and drums used to average $80-$90, sometimes more, each at the local parts store or dealership. They were produced in the respective Country the vehicle was atleast produced in and either met, or exceeded factory quality units. Lots of people used to have their old ones cut & resurfaced, because that would cost about $10-$15 per. They were made of such good quality that you could do this once or twice before tossing them out.

Now, they can be had for as little as $10-$20 each, for almost any vehicle, from a local parts store. This is due to the fact that now, they are made in China, in places where they throw a chunk of the cheapest piece of metal they can get,into a computerized machine. An hour or three later, this machine spits out a whole bunch of rotors or drums. These rotors and drums just barely meet factory spec and standard, if they even do at all. Cuttin/Resurfacing them is not an option when your brakes are worn, because they end up with such a bad lip or wear mark on them that you can't cut enough off to get rid of it. They often come out of the box warped, or warp very shortly after install. Again, due to the poor quality & workmanship invested into them initially.

Reply With Quote
Old 12-30-2009, 11:38 PM
Registered User
Join Date: Jun 1999
Location: Albuquerque, NM USA
Posts: 1,947
Read attachment
Attached Files
File Type: pdf PartsJun05Star.pdf (58.9 KB, 162 views)
Kent Christensen
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles
Reply With Quote
Old 12-31-2009, 12:25 AM
compress ignite's Avatar
Drone aspiring to Serfdom
Join Date: Feb 2004
Location: 32(degrees) North by 81(degrees) West
Posts: 5,554


So,whose the OE supplier to Stuttgart?

[Trick question: is there any Superior Quality Rotor,offered?]

(You guys do realize Kestas is a Forensic Automotive Metallurgist ?]
'84 300SD sold
Reply With Quote
Old 12-31-2009, 04:12 PM
Join Date: Jul 2008
Location: NE Pa
Posts: 102
Originally Posted by dhjenkins View Post
I've seen more than my fair share of rotors that were bad right out of the box. Make sure the shop tests run-out on the new/machined rotor.

Of course, crappy rotors will warp quick as well, due to the inferior metallurgy.
To confirm your claim about "bad right out of the box"...I will relate a story about a brand new 1989 Ford SHO that I purchased...

Both rear rotors were so bad that the wheel hub bearings squealed every time I stepped on the brakes..including the ride home from the dealer the day I bought the car. I finally dial indicated them myself, because they were giving me such a hard time about replacing them..."pads and rotors not covered by warranty"

To do this I trued the outer rotor on a lathe to .000", and measured the runout on the outside edge of the mounting face...much smaller than the rotor in diameter...I got 0.170" runout. You can imagine what the runout was if I trued the minor diameter and measured it on the disc face...maybe double this figure....The callipers and brake pads would prevent the disc from wobbling too much, but the force caused by this deviation was actually flexing the axle shaft, and stressing the tapered roller axle/wheel bearing..causing the squeal.

With new rotors the sound went a way...but at 70,000 miles the right rear axle shaft snapped..while I was doing 75 mph on an interstate highway. An inspection of the sheared axle assembly showed heat blueing all around the failure point, which would have been where the center of the flexing took place.

The left rear had the same issue but not so bad..0.070" runout measured the same way (at the outside of the mounting minor diameter) The left rear had not failed before I finally sold the car. Never assume that because it's "OEM" that it's right...however the odds are still better that it will be more frequently than aftermarket stuff.

Last edited by MDE3; 12-31-2009 at 04:20 PM.
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 12:02 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page