mowog63

Hi All,

I'm replacing the brakes on my 2010 C300 4Matic Sport for the first time and looking for advice people may have and answers to my questions.

I bought Zimmerman rotors and Akebono pads all around.

Questions:
Has anyone bying Zimmerman rotors for a Sport model recently noticed that the cross drill pattern has changed from three holes to two holes?
AuthausAZ told me that this is a design change....
Does everyone replace the caliper bolts when the remove the calipers to replace the rotors?
I've never done this on any other car, but am reading that MB recommends it.

If yes, where is the best place to buy them and what is the torque spec?

If the pads are still ok now, can't I re-use the pad wear sensors with the new pads?

Thanks,
Erik.

c300white

Porsche also recommends caliper bolt replacement. After a lot of heat cycles and if you have salt on the roads - they will
be weaker than original spec. Having said that I don’t think many people replace them - if you are driving at normal speeds and in a no salt area - probably not an issue . Does anyone have a receipt from brake job at dealer that shows them replaced ? Threadlocker is probably also needed.

rocky raccoon

I had a nightmare of a failure on my W123 caused by my not using new caliper bolts on my fronts. Details aren't relevant unless you want to hear. They were properly torqued but over the 300k mile history of the car had probably been on/off many times.

Let me just say that new caliper bolts are cheap and available. Your personal *** is far more expensive. USE NEW BOLTS.

Tom in Austin

Speaking of bolts ... does anyone know where to get the tool needed to take loose the four big bolts that hold the caliper halves together? That is, on the late-model TRW modular cast-iron calipers? I would like to take mine apart to powdercoat the outer half that's visible through the wheel. The modular design means the inner part with the piston - which you can't see in the installed position - can stay connected to the hydraulic line and not be disturbed.

These fasteners are very unusual, they take a 10-point internal bit that looks to be 12 MM across the lobes. I've searched on the web and contacted many specialty tool companies but no one has such a bit available.

95_993

When torqued to spec, the caliper bolts stretch. Repeated torquing to spec can lead to the failure.

IGB

Nicholi2007

Having trouble getting the rear caliper holder bolts off. Did you use a hammer and 18mm wrench?

c300white

The bolts stretch when you first torque them and this is why it is recommended to replace. Porsche and others recommend the same thing too. You also need to use thread lock (some bolts are precoated). Having said that, I reused bolts on my 911 and c300 with no issue. Then again, I am not running autobahn speeds here