Adrianx

How long does the rotors sustain until the replacement? What is the thickness tolerance before replacing?

Semikolon

This depends very on usage and other things like weather, temperature and such. In salty and wet climate they may rust away before they are worn out. In dry climate they will wear out before they rust.

You should be able to read the minimum thickness off the rotor. The minimum thickness is not the same for different rotors, so it's impossible to give a correct answer. The minimum thickness of my front rotors are 22mm, but the rear rotors aren't even close to that thickness when they are new.

RichardM98

The MB rotors are designed to wear more quickly in order to provide the best stopping power. Most people seem to get 2 or maybe 3 pad usages per rotor set. It all depends on how you drive.

Adrianx

well, my dealer was quoting me that it is time for rotor replacement. I did not think it is a set schedule for rotor replacement.
Anyway, I have visibly looked at the rotor on my 2002 E430 4Matic w/ 77k mi and looked at the rotor lips. lips are about 2mm tall, which means the rotor has gone down that much? Break started to squeal and I have the Akebono pads to replace. Should I go ahead and replace the rotor as well or no need for now?

ohlord

will always replace rotors.Are they all mirror smooth?
Break the glaze by hand sanding the rotors with a sanding block and 120 grit paper in a criss cross hatch pattern on both sides,then wash the rotors down with dish soap and water ,rince and dry with a spray of brake cleaner then r/r your pads.If they are not smooth ,you can't turn them so you need new ones in pairs and autohausaz or tirerack has them.Stay away from cross drilled.
Have fun,pay attention,might as well bleed the fluid and flush it all while down there.Pressure bleed only.

MARK CUMMINS

Did The Dealer tell you the Spec of the wear?..It SHOULD have been noted on the repair order.

Buy a Cheap Micrometer at a Harbor Freight or other tool store 1/25MM should work

The MIN Wear spec is stamped on the hub of the rotor as posted above

Double check the dealer spec

Most MB Rotors will do Two sets of pads before they are done

Look into cryo treatment for the replacement rotors..it helps the rotor last longer

Brake rotors with a deep lip/edge can cause a spongy brake pedal...
measure the rotor first...

E420White

I was able to get around 52k miles on my front rotors before they started to show lip/edge. I went through two sets of front brake pads...

I may have been able to get the fronts turned in order to get more usage out of them, but the rotors on a E420 are really inexpensive, so I got new shiny ones...

RichardM98

The lip on the edge of the rotor is caused by the fact that the brake pad surface does not extend all the way to the edge. It should mic at the thickness of the rotor when new.

A 1"/25mm mic will not work on most front rotors because the thickness of the new rotor is over 26mm! In addition, most mics do not have any relief behind the measuring surface to 'clear' the lip. It is necessary to use a spacer. I use a small round magnet (1/2") which I place on the rotor.

For the factory rotors on my W210 I need two mics -- a 1"-2" for the front and a 0-1" for the rear. You could use a 0-2" mic for both but those are less common and so cost more. A less expensive alternative is a vernier caliper. They are cheaper and usually have a 0-6" measuring range. They have the same 'lip' problem so you'll still need a magnet/spacer. MB has a brake caliper guage tool which has the necessary relief behind the measuring surfaces but I'm guessing it's pricey. (Part No. 140 589 00 19 00)

Specs for factory front discs are:

W210.065 with CODE 957 E 36AMG SL*: 25.4mm

W210.020 SL: 22.4mm

W210.025/055/065/072 with CODE 957 E 36,
E 50 AMG W210.070/270 up to 6/99 SL: 25.4mm

W210.072 with CODE 957 E 50 AMG, W210.074,
W210.070 as of 7/99 SL: 30.4mm

* SL = Service Limit means you must change rotors regardless of pad thickness at this point. Add 0.6mm to these figures when changing pads to see if rotors should be replaced.

When they reach these limits, MB factory rotors can not be turned. To do so would make your car unsafe to drive. Better to save money somewhere else so you'll be around when the economy gets better.

Musikmann

Mine were replaced, I think for the 1st time, during a CPO inspection at about 50,000 miles. I supposedly have the entire service history, but cannot see when the pads were replaced or how often. As above, I have read that normally 1 set of rotors is good for 2 sets of pads. As also mentioned above, MB rotors and pads are both soft, hence the brake dust problem. MB has designed a harder pad and I would ask about those; if they have modified the rotors, I have not heard about it.

Adrianx

Well, I have tackled the task to replace rotors and pads for the front. No luck. One of the caliper bolt was siezed up and I end up stripping the bolt hence, it won't come off!
I will have to bring it to mechanic to get the bolt replaced and have them do it all.... $525.00 for the front....
I have brand new Akebono Euro Ceramic pads with MB paste on sitting in my garage now... Mechanic won't use other pads but theirs or MB stock....

Semikolon

well, just get the bolt replaced and then do the job yourself... how did you screw up the bolt anyway?

Adrianx

turning and turning, no grabbing. So, I used the mirror and flashlight to look and yes, it was "Round" and no teeth for the torx 45 to grab....

ohlord

to sears get a set of come outs,drill in turn out,replace bolt.They even have another type with reversed threads that you just screw onto the rounded head and rotate out.Soak in penetrant first.

500bucks is robbery.

e320avangarde

I had same problem on my wheels, non of bolts did not come out .MBenz dealer did not want to have fun with bolts so I was going in almost 4 mech. shops,they were trying to loose them but 2 Mechanics broke the bolt ,and I had a bigger problem, because bolts must be now heated in order to melt them down and free the wheel and change the disc.On the rest bolts mechanic used wd40 and huge torque gun.result was wheels off after 4 hours and permanent damage on two rims due to heating process.
All bolts replaced with new short ones from MBenz cost almost $100 for 4 sets (20 pcs.total)

in your case calipper bolt which was stripped ,I would try to use locking pliers and wd40(spray on it and leave for several minutes to soak) or any other rust free solution and hammer .Take time, do not brake the bolt ,because if you do that you have to buy new calipper too.
If that can not help than use heat to warm up bolt and again locking pliers (in this case be aware bolt will be very hot DO NOT TOUCH IT with fingers.)

Try everything before go to dealer.(because those guys are ripoffssss)

hysonmb

I'm working on my brakes right now and ready to take a rifle to the front rotor! The screw that locks the rotor on stripped while I was trying to get it out, just as one did in the rear, and no matter what I've done to this point it is not coming out. They all seem to be damaged from a previous brake change which I didn't do and now I'm going nuts on what should be a 1 hour job. I just doused it with WD40 and have to go to get a tool to remove the stripped screw. This has been the absolute worst brake change I've ever done because of those little pieces of ......

Air Marshall Eldritch

Sears has that magic stripped screw remover tool for under $20. I think Bob Vila was pitching it a few years ago.