Front Disc and Pad Replacement on Mercedes E-Class W212

Place the vehicle in a flat and stable place, lift it using a hydraulic jack preferably (unscrew the wheel nuts first)

Place the candles in strategic locations (on the vehicle’s cradle or chassis)

Disassemble the Wheels

Using multi-grip pliers and a screwdriver, compress the center of the staple to remove the central stud from its housing, be careful of the spring effect (wear protective glasses)

Gently pull on the sensor plug (if it has not yet warned you via your dashboard, it is logically still good and recoverable, otherwise it will have to be changed)

Then unscrew the socket which is fixed on the caliper using the 8mm Female Torx socket

Using a lever (screwdriver) create a little play between the disc and the pads to facilitate the release of the caliper

Loosen the 2 13 mm caliper bolts (the new ones are sold with the pads)

Release the caliper and attach it to the shock absorber using a tensioner or other means. (Be careful not to damage the brake hose)

Using an 18mm socket, loosen the 2 caliper support bolts (they are very tight).

Loosen the screw holding the disc on the hub using the T30 Torx socket

Remove the disc, if it is seized, put some penetrating oil in the center and tap with a hammer on the center of the disc to make it come out.

Clean the hub using a wire brush or sandpaper to remove residue.

Replace the new disc and screw in the new screw supplied with it.

Open the brake fluid reservoir and make sure it is not full, because when you move the piston back into the caliper, the fluid will rise. If possible, get help for this step so as not to overflow the reservoir (remove fluid if too full using a syringe)

Using a piston pusher preferably or an improvised tool like mine for the occasion, push the piston as far as possible into its housing. Be careful not to damage or jam the dust cover seal.

Check the brake fluid level in the reservoir carefully!!!!

When assembling, out of the 4 pads, 2 are identical: those that go on the outside of the caliper. On the other hand, the pads that fit into the piston on the inside have a direction. On the pads there is an arrow with a letter: L = passenger side and R = driver side

Remove the sensor if salvageable from the old plate and reinsert it into the new one.

I bought the ATE reference with Ceramic coating, but the same ones exist as standard on the site.

Reattach the caliper support with the 2 18mm bolts Place the pads in the caliper (pay attention to the direction) and reinsert the caliper on its support

Place the new screws provided and tighten them using the 13mm socket

Reposition and tighten the wear sensor socket on the caliper

Reconnect the sensor by gently pushing the male plug into the slot

Replace the clip by positioning it and pressing with both hands at the location of the green arrows in order to reposition the stud in its location.

Pump the brake pedal to seal the pads to the disc.

Now you have to do the same thing on the driver's side. This one will be without the wear sensor so it's easier.

For the driver's side, be sure to place the inner pad of the caliper in the piston with the letter "R" but logically that will be the case!

After having done both sides, pump the pedal, top up the level in the reservoir.

Replace the wheels

Put the vehicle back on its wheels and tighten the wheel bolts.

Do a test on a clear road preferably because the first braking is not effective, the discs need to be run in.

The gray paint on the discs will come off, this is normal.