Are Rotors Hard To Change? Beginner guide


I’m a mechanic for more than twenty five years and brake jobs are one of the most common type repairs I perform, but also one of the easiest for the DIY mechanic to nail successfully at home. You are in the right place, and 5 mins from now you’ll be an expert.

Replacing brake rotors is not a difficult auto maintenance task. A DIY mechanic may successfully replace brake rotor in under two hours. Tools required include ratchet, socket set, wrench set, hammer, jack and axle stand.

In this post we’ll cover everything you need to know in order to nail rotor replacing successfully. We’ll cover: Tools needed; rotor removal; rotor fitting; pad fitting; brake noise prevention; bedding in brake process.

Tools Needed

New Rotors

For most, the tools required to replace rotors are the type tools a DIY mechanic would ordinarily have. We’ll cover them here in a little more detail.

Most vehicles run rotors front and rear. Since front rotors work harder than rear, they wear out more frequently.

In any event, this post will cover replacing both front and rear rotors. Note, replacing rear rotors may require a brake caliper wind back tool or hand held service tool (I’ll show you how to figure out if you need these later) and so I’ll list tools and supplies required for front and rear rotor replacement separately.

You’ll find all these tools and supplies on the “Brake repair tools page” and if you need brake parts, check out the Parts Geek link below.

Get up to 80% Off Dealer Prices on Brakes Replacement Parts! Shop Now at Parts Geek!

Front rotor tools and supplies

  • Socket set
  • Ratchet
  • Breaker bar
  • Torque wrench (optional)
  • Long flat screwdriver
  • Bungee
  • Hammer
  • Wire brush
  • Blue thread lock
  • Brake cleaner
  • Permatex brake pad lube
  • Silicone grease

Rear rotor tools and supplies

Wind back tool
Rear caliper wind back tool
  • Hand held scanner (vehicles with electric parking brake (EPB))
  • Wind back tool (vehicles with wind back calipers)
  • Socket set
  • Ratchet
  • Breaker bar
  • Torque wrench (optional)
  • Long flat screwdriver
  • Bungee
  • Hammer
  • Wire brush
  • Blue thread lock
  • Brake cleaner
  • Permatex brake pad lube
  • Silicone grease

Front Rotor Removal

Front rotor wear is more common than rear, and that’s no surprise since they carry the weight of the vehicle under braking. Most vehicles employ what’s known as free floating brake calipers, as they’re the most common type, I’ve used them in this guide. The less common fixed caliper may be fitted to larger commercial vehicles, high performance cars and classic.

Floating brake caliper

The rotor removal process looks like this:

  • Park vehicle on level hard surface
  • Loosen lug nuts
  • Jack vehicle
  • Fit axle stand
  • Remove wheel
  • Loosen rotor face fastener (Torx or Star head)
  • Turn steering wheel fully outwards
  • Open hood and loosen brake fluid reservoir cap
  • Using flat screwdriver slowly lever the piston backwards
  • Remove caliper clip (if fitted)
  • Loosen brake caliper fasteners
  • Remove brake pad sensor wire (if fitted)
  • Remove caliper and suspend from coil spring using bungee
  • Remove brake pads and discard (note pad clip location, if fitted)

So far the story is pretty typical of all free floating calipers. For some lucky DIYers, the rotor can be removed at this stage, Nice!

However, most will need to go one step further and remove the brake caliper carrier. The carrier is easily identified as it’s the metal component the brake caliper is/was fastened to.

Brake component guide

Brake carrier removal as follows:

  • Using a breaker bar, loosen both carrier fasteners (located behind the wheel knuckle)
  • Remove the carrier

You’re now free to remove the rotor. However, on occasion the rotor may remain stuck to the hub. If this sounds like your problem, the solution is as follows:

Note we’ll be striking the rotor, so best to wear eye protection in addition if your vehicles lug nut threads are exposed, thread the nuts on a turn to help protect the threads from a potential damage when using the hammer.

  • Using a ball head hammer (preferred), strike the rotor sharply, head on, around the hub

Front Rotor Fitting

Cleaning new Rotors

Rotors are bare metal and prone to corrosion. Since no body wants to buy rusty rotors, they are given a light coat of primer and a coat of wax as part of the manufacturing process.

The primer has no negative effects on new brake pads but the wax does. It is therefore mission critical we remove the protective wax coating before fitting the rotor. To clean the wax coating, spray the rotor both sides with brake cleaner and wipe clean with a clean cloth.

The rotor fitting process as follows:

  • Using wire brush, remove loose rust from the hub rotor interface
  • Fit the rotor and fit the rotor fastener (Torx or Star screw)
  • Remove brake pad clips and discard, if new clips supplied with new pads (otherwise clean and refit)
  • Using the wire brush, clean the brake carrier rails (use dust mask)
  • Refit old clips or refit new
  • Use Permatex brake on both rail clips
  • Using wire brush, clean both carrier fastener threads and add thread locker
  • Fit carrier and fit fasteners
  • Torque carrier fasteners to spec (typically 75 lb. ft. 100 Nm)

Front Brake Pad Fitting

New brake pads fitted

Fitting front brake pads is easy and no special tools are needed. The procedure is as follows:

  • Check pad markings, some may be left side right side sensitive or fitted with a brake sensor
  • If pads come with new pad clips go ahead and fit them
  • Test fit pad
  • Remove pad and apply Permatex anti squeal paste to rear
  • Fit pads
  • Fit caliper (if caliper won’t fit – push piston fully home)
  • Clean caliper pins and apply silicone grease
  • Fit new caliper fasteners (if supplied), otherwise clean and fit old ones adding blue thread lock
  • Torque to specification typically 20 lb. ft. (28 Nm)
  • Plug in break sensor (if fitted)
  • After completing both sides, refit brake fluid reservoir cap
Important – PUMP BRAKES BEFORE MOVING VEHICLE

That’s it, see bedding in new brakes below.

Rear Rotor Removal

Worn out brake rotor

Many vehicles today are fitted with an integrated parking brake caliper. It simply means the rear calipers do two jobs, they activate with the brake pedal, but they also activate with parking brake application. This means we need to treat this system a little differently than we do the front calipers.

In addition, how the parking brake is activated makes an additional difference in how we approach rear rotor replacing.

Rear rotor removal is for the most part the same as the front. However, some steps may differ depending on what type parking brake your vehicle employs.

For the purpose of this guide we’ll assume your vehicle is equipped with the rear caliper integrated parking brake, since most are.

That said there are two common methods of activating the parking brake:

  1. Manual – conventional manual operated handle or foot lever
  2. Electronic – electronic parking brake (EPB), identified by a push button activation

Manual activation – If your vehicle employs a standard manually operated brake, then rear caliper pistons can’t be pushed back they must instead be wound back. A special tool known as a wind back tool is required in order to retract the rear caliper piston.

Electronic – If your vehicle is fitted with EPB, a scan tool is required in order to place the parking brakes in service mode. It isn’t possible to simply push back rear caliper pistons, they must be wound back and only after placing the system into service mode.

Manual parking brake activation – rear rotor replacing

This process is near identical to the front rotor replacing process covered earlier and so I won’t repeat it here. The process has an additional step. As said it does require a tool known as a wind back tool and you can find that tool here on the “Brake repair tools page”

The additional step is needed to retract the caliper piston, the process is as follows:

  • With the rear caliper removed, fit the correct size wind back tool adaptor, to the piston
  • Winding the tool (simultaneously winds and compresses the piston)
  • When full retracted, remove the tool

The rest of the process is identical to front rotor fitting.

Electronic parking brake activation – rear rotor replacing

If your parking brake activates automatically or you press a button to activate it, you have an EPB system. Before working on this system, you will need a bidirectional scan tool and a wind back tool in order to replace the rear pads and rotors. You can find all the tools you’ll need to perform this repair here on the “Brake repair tools page”.

Scan tools

The process is as follows:

  • Using a bidirectional, plug the tool into the OBD port (under dash)
  • Turn ignition to position 2
  • Select parking brake service function
  • Set parking brake to “Service mode”
  • Turn ignition off

From here the process is identical to the manual process, i.e. you’ll need to use the wind back tool to retract the pistons before moving on to rotor replacing.

After replacing the rotors as per the process described earlier, go ahead and reverse the service mode process by turning service mode “Off”.

Ideally all wheels should be torqued to specification Cars usually run around 75 lb. ft. (100 Nm) – SUV and trucks approx. 100 lb. ft. (135 Nm)

Bedding In Brake Procedure

Your new pads and rotors won’t feel effective until their surfaces mate. That usually occurs after six to ten on road brake applications but that can vary.

The bed in procedure is important, especially after caliper pistons have been fully retracted. Before moving your vehicle, pump the brake pedal must be pumped several times to push pistons out to meet pads.

If you fail to pump the brake pedal before moving YOU WON’T HAVE BRAKES

Bed in process as follows:

  • Before moving vehicle, pump brake pedal until brake pedal feels firm (usually 3 or 4 pumps)
  • Now go-ahead and check the brake fluid reservoir level (should read max)
  • Move the vehicle a few feet and apply brakes to test
  • Move to a quiet road and from 30 – 40 mph perform a normal brake applications, repeat 6 to 8 times (Avoid hard braking)

At this point the brakes should feel great. Last job is recheck the brake fluid level.

You are now a pro!

John Cunningham

John Cunningham is an Automotive Technician and writer on Rustyautos.com. I've been a mechanic for over twenty years, I use my knowledge and experience to write articles that help fellow gear-heads with all aspects of classic car ownership, from tires to roof aerials and everything in between.

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