2013-2016 Mercedes-Benz C300 Brake Job Tools and Torque Specs

By Core Brake Parts Tech Team — Circleville, OH warehouse

A brake job on a 2013-2016 Mercedes-Benz C300 needs a short list of metric sockets, two Torx bits, a hex bit for the W205 rear guide pins and, above all, a torque wrench plus an angle gauge. The catch is that this year range covers two different cars: the 2013-2014 C300 is the W204 generation and the 2015-2016 C300 is the W205, and their fasteners and procedures differ. This guide lays out the tools for each, the one published torque procedure we could verify, and where to get the rest.

First, Which C300 Do You Have?

The 2013-2014 C300 is the W204 body (the 3.5L V6), and the 2015-2016 C300 is the W205 body with the 2.0L turbocharged four-cylinder. Brake parts do not interchange between them, and the fasteners are not the same either. Confirm the model year before you buy parts or pick up a socket. On the W205, also note whether the car has the AMG Sport package: several pad and rotor part numbers are split by that option.

Tool List for the 2013-2014 C300 (W204)

The W204 front caliper is held by two 13 mm bolts that thread into 17 mm nuts, so you need a 13 mm socket on a ratchet and a thin-profile 17 mm wrench to hold the nut. The caliper bracket comes off with an 18 mm socket, and a long-handled ratchet helps because those bolts are tight. The rotor itself is held to the hub by a single T27 Torx screw. At the rear, the slide bolts are T45 Torx under rubber boots, the bracket bolts are 18 mm (some cars use Torx heads instead) and the pad wear sensor is held by an 8 mm bolt or a plastic fitting.

• 13 mm, 18 mm and 8 mm sockets, plus a ratchet with a long handle
• 17 mm thin-profile wrench
• T27 and T45 Torx sockets
• Caliper piston compression tool (a C-clamp and an old pad also works)
• Floor jack, jack stands and a caliper hanger
• Flat-head screwdriver and needle-nose pliers for the pad retaining clips
• Rubber mallet for a rotor that is rusted to the hub
• Micrometer or digital caliper if you want to measure rotor thickness
• Brake cleaner and brake-specific grease for the pad contact points

On the front, the wear sensor connector is on the passenger side; unplug it before you lift the caliper off. Push the piston back slowly and watch the fluid reservoir, because the level rises as the piston retracts. On the rear, the pad retaining clips pry off first, and the inner pad has a three-prong clip that snaps into the piston. The W204 3.5L front rotor we carry is the EBC Ultimax OE-style front rotor set RK1531 for the 2013-2014 C300 3.5.

Tool List and Rear Procedure for the 2015-2016 C300 (W205)

The W205 rear brake has an electronic parking brake in the caliper, and it must be retracted before you can push the piston back. Sit in the driver seat with the door shut, press the start button to the first position, hold the phone and OK buttons on the steering wheel for about five seconds, choose Brake Pad Replacement in the cluster menu, confirm, and wait for the rear parking brake to retract. Never force the piston back with the parking brake applied.

• 17 mm socket for the wheel bolts
• 18 mm socket or wrench for the caliper bracket bolts
• 7 mm hex bit socket for the guide pins
• T30 Torx bit for the rotor set screw (seat it fully so the screw does not strip)
• Torque wrench and a torque angle gauge
• Caliper piston compressor, caliper hook, flathead screwdriver for the anti-rattle clip
• Hammer and a wire brush or wire wheel for the hub face

The sequence is anti-rattle clip off, rotor set screw out, guide pin dust caps off, guide pins out, wear sensor pulled off the pad, caliper lifted and hung, then the two 18 mm bracket bolts and the rotor. Only the passenger-side inner pad carries the wear sensor, so move it to that pad on reassembly and route the connector over the top of the caliper. For W205 rear parts we stock the DBA Street Series T2 slotted rear rotor for the 2016-up C300, and for AMG Sport package cars the EBC Redstuff ceramic low-dust rear pads or the more aggressive EBC Yellowstuff street and track rear pads.

Torque Specs: What We Could Verify

For the W205 rear caliper bracket bolts, the published procedure is 60 Nm (44 ft-lbs) plus an additional 45 degrees of rotation. That is a torque-plus-angle spec: tighten to 60 Nm with a torque wrench, then turn each bolt a further 45 degrees using an angle gauge. A torque wrench alone cannot do this step, which is why the angle gauge is on the tool list.

We did not find a manufacturer-sourced figure we could confirm for the W205 front caliper, the W204 caliper and bracket bolts, the guide pins or the wheel bolts on either car, so we are not printing numbers for them. Torque those to the values in the Mercedes-Benz service information for your VIN, which a dealer service department can look up for you. Guessing a bracket bolt value is not worth the risk: an under-torqued bolt can back out, and an over-torqued one can stretch or strip its threads.

Two general rules apply to both generations. Brembo's fitting instructions say not to use an impact tool on these fasteners, and to always replace self-locking screws, nuts and safety elements rather than reuse them. Ask the service information whether the W205 rear bracket bolts are single-use before you reinstall the old ones.

Rotor Install Steps That Prevent a Pulsating Pedal

Many comebacks after a brake job are caused by runout, not by bad parts. Rust on the hub face tilts the new rotor, and the pads then wear it unevenly.

1. Clean the hub mounting face of rust and deposits with a wire brush or wire wheel, and keep oil and grease off it.
2. Clean the caliper bracket where the pad clips sit.
3. Fit the rotor and secure it with the Torx retaining screw (T27 on the W204, T30 on the W205 rear).
4. If you have a dial indicator, measure runout about 5 mm in from the outer edge with the rotor clamped by a few wheel bolts. Brembo's limit for passenger cars is 0.10 mm per revolution. If it is over, check the hub face again and re-seat the rotor.
5. Hand-start the bracket bolts to avoid cross-threading, then torque them to spec.

What to Replace Together

Replace pads in axle sets and do pads and rotors together on the same axle, which is how the W205 rear job above is laid out. Fit a new wear sensor whenever the old one has worn through or its wire is damaged, since a cut sensor keeps the warning lamp on. Check the guide pin boots and slide action while the caliper is off. To match the other axle, browse our brake rotors and brake pads. After the job, follow the bedding instructions in the pad box. Without them, Brembo recommends at least 200 km (125 miles) of gentle, sparing braking.

Frequently Asked Questions

Do I need a scan tool to do the rear brakes on a 2015-2016 C300?

No. The W205 lets you retract the electronic parking brake from the instrument cluster menu using the steering wheel buttons. A scan tool can do the same job, but the built-in Brake Pad Replacement mode is enough.

Are 2013-2014 and 2015-2016 C300 brake parts the same?

No. The 2013-2014 car is the W204 and the 2015-2016 car is the W205, with different calipers, fasteners and rotors. Buy parts by model year, and on the W205 by whether the car has the AMG Sport package.

What does 60 Nm plus 45 degrees mean?

Tighten the bolt to 60 Nm with a torque wrench, then turn it an additional 45 degrees with an angle gauge. The angle step sets the final clamp load, so it cannot be skipped or estimated by feel.

Can I use an impact wrench on the caliper bracket bolts?

Not to tighten them. Brembo's instructions say not to use impact tools on these fasteners. Tighten them with a torque wrench to the specified value.

Which side has the brake wear sensor?

On the W205 rear, only the passenger-side inner pad has the sensor. On the W204 front, the sensor connector is also on the passenger side and must be unplugged before removing the caliper.

Sources

1. FCP Euro - Mercedes W205 rear brake pads and rotors - W205 tools, parking brake service mode, wear sensor location, 60 Nm plus 45 degree bracket bolt torque
2. MBWorld - C-Class (2007-2014) brake pads and rotors - W204 socket and Torx sizes, front and rear procedure
3. Brembo - Instructions for replacement of brake disc - hub cleaning, 0.10 mm runout limit, no impact tools, replace self-locking fasteners, 200 km run-in