Pelican Parts
Mercedes-Benz Parts Catalog Accessories Catalog Mercedes-Benz How To Articles Mercedes-Benz Tech Forums
Call Pelican Parts at 888-280-7799
View Recent Cars  |Shopping Cart Cart | Project List | Order Status | Help
 >  >
Front Brake Pad Replacement
 
Bookmark and Share

Pelican Technical Article:

Front Brake Pad Replacement

Steve Vernon

Time:

2 hours2 hrs

Tab:

$60 to $200

Talent:

**

Tools:

13mm socket, pliers, E10 Torx, large flathead screwdriver, C-clamp, floor jack, jack stands, wheel chocks, safety glasses

Applicable Models:

Mercedes-Benz C250 (2012-14)
Mercedes-Benz C300 (2008-14)
Mercedes-Benz C350 (2008-14)

Parts Required:

New pads

Hot Tip:

Use new hardware

Performance Gain:

Car stops better

Complementary Modification:

Replace Rotor or disk

In general, you should inspect your brake pads about every 25,000 miles or once a year, whichever is less, and replace them if the material lining of the pad is worn down enough to trigger the pad replacement sensor, or there is less than a quarter inch of material on the pad. In reality, most people don't inspect their pads very often, and usually wait until they see the little brake-warning lamp appear on the dashboard.

If you let the pads wear down enough you will get to the point of metal on metal contact, where the metal backing of the pads are contacting the brake discs. Using the brakes during this condition will not only give you very dangerous and inadequate braking, but will also begin to wear grooves in your brake discs. Once the discs are grooved, they are damaged and if you have drilled or slotted rotors there is no way to repair them. The smart thing to do is to avoid this problem altogether and replace the pads at the correct times.

Safely jack up and support the front of the vehicle and remove the front wheels. Please see our article on safely lifting and supporting your Mercedes W204.

Brake pads should always be replaced in pairs. If you have not bled your brakes in a while this is a good time to give them a good bleed and get fresh fluid in the system. Please see our article on bleeding your brakes.

The front brakes on the W204 have a floating or sliding caliper (yellow arrow).
Figure 1

The front brakes on the W204 have a floating or sliding caliper (yellow arrow). This means the caliper is attached to the mount by sliding bolts (red arrows) and has only one piston on one side of the caliper (green arrow). As pressure is applied to the pads by the caliper piston the caliper slides or floats along the slide bolts to transfer the clamping force to both the piston pad and the pad on the other side.

To change out the pads begin by removing the brake pad wear sensor from the holder on the right side caliper (red arrow) by pulling it straight out and then remove it from the pad (yellow arrow).
Figure 2

To change out the pads begin by removing the brake pad wear sensor from the holder on the right side caliper (red arrow) by pulling it straight out and then remove it from the pad (yellow arrow). You should be able to pull it from the pad by hand but if it is stuck use a set of small needle nose pliers to remove it, using care if you are planning on reusing the sensor. If you are changing your pads before the wear sensor has activated there is no reason why you cannot reuse it but if it has worn down you should replace it.

While it is not necessary to remove the wear sensor housing from the caliper I like to use an E10 Torx to remove the housing and get it out of the way.
Figure 3

While it is not necessary to remove the wear sensor housing from the caliper I like to use an E10 Torx to remove the housing and get it out of the way.

If your calipers still have the vanity plate simply pull it straight out from the two holes it sits in (red arrows).
Figure 4

If your calipers still have the vanity plate simply pull it straight out from the two holes it sits in (red arrows).

Next, use a large flathead screwdriver and a set of pliers to remove the pad retention spring (red arrow).
Figure 5

Next, use a large flathead screwdriver and a set of pliers to remove the pad retention spring (red arrow). Grasp the spring with the pliers to save it from flying off; the spring is under a fair amount of tension so you do not want it flying off the caliper. With a good hold on the spring use the screwdriver to pry the spring off walking it outwards until it is free from the caliper.

Use a 13mm socket and remove the two slide bolts (red arrows).
Figure 6

Use a 13mm socket and remove the two slide bolts (red arrows). Your new brake pad set should include four new bolts (two for each side).

The slide bolts are single use only and are microencapsulated from the factory.
Figure 7

The slide bolts are single use only and are microencapsulated from the factory. Always replace the braking hardware when servicing your brakes.

Depending on how worn your rotors and pads are you will need to compress the piston back into the caliper.
Figure 8

Depending on how worn your rotors and pads are you will need to compress the piston back into the caliper. Use a large flathead screwdriver and place it between the caliper and rotor and push the caliper outwards (red arrow), which will force the piston back in. Never place the screwdriver around the piston, as you can damage it or the rubber boot.

While you are pushing the piston back in you will be forcing brake fluid back into the system and up into the reservoir.
Figure 9

While you are pushing the piston back in you will be forcing brake fluid back into the system and up into the reservoir. Make sure to check the fluid level in the reservoir as you do this, and be prepared to remove some fluid as needed.

You can now remove the caliper from the mount.
Figure 10

You can now remove the caliper from the mount. Be prepared to hang the caliper or place it on something at a height that will not put any stress on the brake hose or line. Never let the caliper hang from the brake line.

You will need to push the piston all the way back into the caliper to install new pads.
Figure 11

You will need to push the piston all the way back into the caliper to install new pads. Before you remove the old pad use a large C-clamp and compress the piston all the way in remembering to check the level of fluid in the reservoir.

The pad on the piston side will come with metal clips that hold it in the position in the caliper and piston.
Figure 12

The pad on the piston side will come with metal clips that hold it in the position in the caliper and piston. Pull the old pad out and press the new pad in. The pads will be marked F for front and R&L for right and left.

The outside pad will come with an anti-squeal pad on the back; this is just a sticky material that helps hold the pad in place and prevents squeals.
Figure 13

The outside pad will come with an anti-squeal pad on the back; this is just a sticky material that helps hold the pad in place and prevents squeals. Push the old pad off the caliper. Clean up any residue form the old backing and install the new pad. Installation is the reverse of removal. Once everything is back together pump the brake pedal a few times to move the pads into position against the rotor. Always follow the breaking in instructions that will come with your new pads. New pads need to be broken in properly and will have diminished braking capabilities until they are.



Bookmark and Share

QUICK LINKS
About Us
Careers
Pelican Parts, Inc.
1600 240th Street
Harbor City, CA 90710
Order Online or Call:
888-280-7799
CONNECT WITH US
NEWSLETTER
Sign Up for Pelican Pit Stop News & Special Offers
Page last updated: Thu 2/23/2017 03:03:58 AM