Disc Brakes (Lines, Pads, & Rotors)

Last Updated - April 10th, 2005

So your brakes are grinding and squeeling to beat hell and you don't really want to pay someone else $500+ to do them for you.  Brakes are all that stand between you and the bumper of the car in front of you, so you don't want to skimp here or do a half assed job.  Please re-read that last sentence.  Still, they aren't really that difficult to replace.  ...and they don't cost as much when you do it yourself.

Click on a picture to enlarge it.

Instructions:

There are various degrees of brake jobs so you may not do all of this depending upon what you intend to change.  You could upgrade just the brake lines.   You could keep your lines and just change your pads.  You could just change your pads & rotors.  You could just swap out a frozen caliper.  This is your call.  Generally, if you're replacing your pads, you should at least have your rotors turned.  Calipers are surprisingly cheap to replace so if you have any doubts about the ones you have, just replace them.  ...and if you have to bleed the brake system anyway, you may just want to change the lines for good measure or go with stainless steel lines.  Regarless, this is your call.

Inspection (What do I NEED to do?)

Excessive brake noise, poor braking performance, and a pulsing brake pedal are all signs that you need to look at your brakes.   Ed and Mike aren't brake experts by ANY stretch, but the following are some tips:

In car driving inspection:

• Brake pads are generally equipped with a piece of metal on them that scrapes the rotor when the pad is overly worn.  This is an audible alert telling you to do something.  You may also hear the heads of the rivots squeeling on the rotor if the pad is too thin.  (Note:  Don't confuse this with the grinding sound your brakes initially make on a wet day or when the car hasn't been driven for a few days.  If that sound goes away during use, it is simply rust on the rotors that rubs off after a few stops.  If there's a heavy grinding sound and it doesn't go away, YOU HAVE A PROBLEM!)
  
• A pulsing brake pedal (especially under partial brake application) is a sign that your rotors are warped and need to be replaced.
  
• Pulling to one side during braking or bad overall braking performance is indicative of one or both sides needing attention.
  
• Reduced brake effectiveness when driving through mountains or lots of hills is a sign of brake fade and can be caused by overheated pads or by moisture in the brake fluid itself which allows the fluid to boil under braking heat.
  

Out of car inspection:

• If the rotors on both sides of the car show a deep groove from the pads, it's probably time for new rotors.  
  
• If only one side of the car has a deep groove and the other is relatively smooth or just rusty, you may have a frozen caliper on the smooth side.  (Your braking will also stink if this is the case.... ask Mike who drove around this way for several thousand miles.)
  
• The other thing you can look at is the thickness of the pads.  If they look to be less than 1/4" thick, they are showing some wear.
• You can also look at the lines and see how they look in general.
• You can bleed one of the brake lines a little and see what color the fluid is that comes out.  If it's a yellow "light beer" color, it's probably fine.  If it looks like an "amber", a "stout", or Coca Cola -or- if it has air bubbles, it's time to replace it.  Because the fluid picks up moisture over time, it's worth your time to go ahead and replace it when performing other brake related maintenance.
  

Brake Lines

If you're doing your brake lines, then you'll need to replace your brake fluid and bleed the system.  That would be a good time to do everything too while you're in there.

1.  Put a pan under the caliper of the wheel you're working on to catch the brake fluid.

2.  Unbolt the end of the brakeline from the caliper and let the fluid drain into the pan.

3.  Pull out the tab between the body side steel brake line and the caliper side (generally rubber) brake line.
This is a "U" shaped tab that slips between one side of the brake line and the bracket that holds it in place.  The tab will pull straight out but will probably be rusted.  You can generally get a short pry bar under the lip and use a hammer on the pry bar to knock the tab outward.  Then you can wiggle it off with a pair of pliars.

4.  Unscrew the caliper side brake line from the body side brake line. 
When doing this, use 2 wrenches.  Hold the body side brake line as still as you can to avoid breaking it.  It will snap VERY easily. 

5.  New lines install in the reverse order.  If you are doing your calipers & other brake parts, do those next while the caliper end of the brake lines are disconnected.  Otherwise, reconnect them and then proceed to the brake bleeding procedure.

Front Disc Brakes

1.  If you intend to replace your brake lines see the Brake Line proceedure first.

2.  If you intend to replace your calipers and you aren't replacing your lines, put a pan underneath the caliper and remove the bolt that holds the end of the brake line to the caliper, and allow the fluid to drain.

3.  Remove the 2 retaining bolts that go through the boots in the back of the caliper.  Don't worry, it won't just fall off.

4.  If you've left the brake line attached to the caliper, you will need to suspend the caliper via a piece of wire, a coat hanger, cable tie, or whatever.  Generally it's easiest to just tie it to the coil spring once you break it loose.

5.  Remove the caliper.
The top of the caliper assembly should rotate away from the rotor with the bottom still in place.  Generally it will move a little but not come off all the way because the rivots on the inside pad catch on the inside of the caliper cylinder.  You can gently pry at this with a flat blade screwdriver and push the cylinder in enough to free the assembly.  You may also need to do a little wiggling with a pry bar, but in general, this shouldn't be a high effort operation. 

If you are replacing the calipers, themselves, make sure to hang onto some of the hardware (rather than returning it with the core).  You need to make sure you hang onto the caliper bolts, the brass sleeves from inside caliper boots, the pad anti-rattle spring, the brake line bolt, the 2 brass washers, and the rubber bulb that fits over the bleeder screw. 

6.  Slide/Bend the ends of the retaining spring/clip up off the pads so that you can remove them.
Do not lose this spring.

7.  Remove the outter pad.
Remember which one this is so that you can compare it to the pads you are putting on in order to identify which one goes where.  This will not be at all obvious once you remove both of them.

8.  Remove the rotor.
The rotor should pull straight out without any effort as it just floats on the wheel bolts.

9.  Remove the inner pad.
Remember which one this is so that you can compare it to the pads you are putting on in order to identify which one goes where.

10.  If you wish, you can install new sleeves in the caliper boots now.  Whether you replace the sleeves or not, you should lube them with caliper grease (between the sleeve and boot.  This is a messy process because the boot likes to scrape the grease back off the sleeve.

11.  Reassemble with new parts in the reverse order.
As you're doing this, you may need to look at the pics in the table above in order to ascertain which pad goes on which side and how they are oriented.  It won't be obvious by just looking at them, and that's why we posted so multiple pics from multiple angles.  Here they are again (1, 2, 3, 4, 5).

12.  Proceed to Rear Disc Brakes if you're doing those too.  If you drained the brake fluid and aren't doing the rear brakes, proceed to the brake bleeding proceedure.

Rear Disc Brakes

The rear disc brakes are similar to the front.  In general, the calipers and pads are just smaller but work the same exact way and can use identical replacement hardware (sleeves & bolts). 

The major difference with the calipers is that the pads are not retained by the caliper adapters but by the calipers themselves.  The piston side pad has a spring insert that holds it in place.  You can pull the old one straight out and force the new one in.  The outer one clips to the outer edge of the caliper.  Thus, this is one piece when assembled unlike the front where the caliper slips over the pads & rotor.

The rear rotors are also different.  There is a small drum brake in the center that is used by the parking brake.  Thus, if you want to remove the rotor, you need to release the parking brake.  Make sure your car isn't going to roll and that your front wheels are properly blocked before you do this. 

1.  If you intend to replace your brake lines see the Brake Line proceedure first.

2.  If you intend to replace your calipers and you aren't replacing your lines, put a pan underneath the caliper and remove the bolt that holds the end of the brake line to the caliper, and allow the fluid to drain.

3.  Remove the 2 retaining bolts that go through the boots in the back of the caliper.  Don't worry, it won't just fall off.

4.  If you've left the brake line attached to the caliper, you need to suspend the caliper via a piece of wire, a coat hanger, cable tie, or whatever.  Generally it's easiest to just tie it to the coil spring once you break it loose.

5.  Remove the caliper.
Unlike the front, the pads will come off with the caliper as you rock it out of position.

Also, the rear may be assembled with slightly smaller bolts than the front.  These can be EASILY be snapped off with a 3/8" wrench.  If you're replacing the hardware, the same size bolts you use in the front will fit fine on the rear.

6.  Remove the rotor.
If the parking brake is released and it isn't rusted to the wheel hub, you can pull it right off.

If you can't budge it make sure the parking brake isn't set and that your vehicle isn't going to roll on you.  Then try again. 

If it's pretty clear that it isn't going to move (this appears to be common), remove the domed cap, the cotter pin, and the locking "castle". Undo the axle nut (27mm), remove the outter wheel bearing being careful not to contaminate it with debris, and then pull the rotor off with the hub rusted to it.  Once both pieces are off, place the  the assembly on top of some blocks so that the rotor is supported and the hub is suspended below it.   Then take a hammer to the end of the wheel bolts on the hub being careful not to hit the threads.  The two pieces should come apart after a few good whacks.  If a wheel bolt comes out, don't worry, you can put it back in after the two pieces separate (should be self explanitory by looking at it).  Note, the new rotor will not need to be hammered onto the hub.  Also note that the wheel nut does NOT have to be he-man tight like the front does because in the rear, the nut is compressing the bearings.  To seat the bearings, torque the nut down to ~25ft-lbs, and then back it off 1/4-1/2 a turn so that it's finger tight.  (By contrast, the front axle nuts are speced at 180 ft-lbs)

7.  Replace the parking brake shoes or adjust the parking brake shoe width as needed.  (See Parking Brake Section.) 

8.  Reassemble everything in the reverse order.

Parking Brake

The parking brakes look complicated until you tear into them.  At that point, you realize that they consist of 2 shoes, 2 springs, and a set screw.  They aren't all that complicated at all.

1.  If you don't already have the rear hub and rotor off, see the Rear Disc Brake section for instructions.

2.  Turn the thumb wheel on the set screw until the shoes are pulled in as closely as possible.

3.  Remove one of the clips from one of the two parking brake shoes.
This can actually be done with your fingers if you grab on just right.  Hold the tip of the pin with a pair of pliars so that the long direction is horizontal.  Then use your fingers to rotate the clip 90 degrees until it pops off.

4.  Next, pull outward a little on the top of the shoe and remove the upper spring that connects to the top of the shoe.
When reinstalling, remember that the spring goes BEHIND the shoes.

5.  Now disconnect the lower spring.

6.  Remove the shoe.
(At this point it really just falls out)

7.  Unclip the second shoe and remove it.

8.  Wiggle the set screw halves off of the brake shoes.

9.  Wiggle the set screw halves onto the new brake shoes.
You'll find that these don't just slip on.  Push them on as far as you can and then whack them on the ground while holding the shoe.  The tapping will fully seat them.  During reassembly, you can adjust the positions by tapping the ends with a wrench or hammer.

10.  Install one of the new shoes with the clip.
You can actually compress these with your fingers if you grab them right.

11.  Connect the bottom spring to the installed shoe, fit the bottom of the second shoe into place, and connect the other end of the spring to it.  (Like this)
Most likely, you'll need to adjust the halves of the set screw so that they line up.  Just tap them with a wrench or hammer.

12.  Swing the 2nd shoe up into position and secure it with the clip.  (Like this)

13.  Use the set screw to extend the shoes to a diameter of 6-3/4 inches.

14.  Reassemble the rear hub/rotor.


Bleeding the brakes

Once all of the brake lines have been firmly reconnected and you're done with everything else, you need to add brake fluid and bleed the brakes.  Starting with the wheel furthest from the master cylinder (rear passenger side) and working in to the closest one, perform the following procedure.

1.  Open the bleeder screw in the back side of the caliper approximately 1 turn. 
This is the brass screw shown on the right caliper in this picture.  The left caliper has the screw capped with a rubber stopper.

2.  Insert the pointy end of the bleeder hose on your bleeder kit into the opening in the bleeder screw.

3.  Use the magnetic mount to support the bleeder bottle in a position so that it is above the caliper allowing air bubbles to run up the tubing to the bottle.

4.  Fill the master cylinder resevoir with fresh brake fluid.

5.  Gently pump the brake pedal ~10 times.
If you stomp the pedal, the bleeder hose will blow off and you'll spray brake fluid everywhere.

6.  Go look at the tubing connecting to the bleeder bottle. 
If you've got air bubbles, you need to repeat the procedure until the air bubbles are gone.  On Mike's IROC, this took about 20 rounds at the rear passenger side caliper.  The bubbles will get smaller and smaller and fewer and farther between.  Eventually they will all go away. 

With Mike's bleeder kit, the bottle fills up after pumping the pedal around 12-15 times.  Keep in mind that as you do this, fluid is also draining from the master cylinder resevoir which doesn't hold all that much fluid in the first place.  You want to make sure it stays as full as possible.  The first two or three times you fill up the bleeder bottle on each corner of the car, you should probably just dump the fluid as it may be contaminated with old fluid.  After that, you can start dumping it back into the master cylinder resevoir between rounds of pumping.  As you do this, you may want to top it off with additional fresh fluid as needed.  Lastly, keep the resevoir cap closed when you aren't adding fluid to help keep the moisture from the air out.
7.  Once the bubbles are gone, close the bleeder screw and replace the rubber stopper to keep dirt out.

8.  Repeat this process for each caliper moving inward toward the master cylinder.
(Rear Passenger Side, Rear Driver's Side, Front Passenger's side, Front Driver's Side)  As you move in closer to the master cylinder, you will find that it takes fewer rounds of pumping to get the air out.  This is because the tubing is shorter between the master cylinder and the caliper. 

Tools Required:

• Brake Bleeder Kit
• 3/8" rachet with sockets
  
• 27mm  socket for rear wheel nuts (if rotor is rusted the hub)
  
• Hammer
• Flat blade screw driver
• Small pry bar
• 2 open end or adjustable wrenches for connecting/disconnecting brake lines.
  

Supplies to Remember:

• Caliper Grease
  
• DOT 3 or above Brake Fluid (get the big 32oz bottle)
• Remanufactured Front Calipers (Front ones after the core return are very cheap)
• Remanufactured Rear Calipers (Special order item so plan in advance if you want these)
• New brake pads
• New rotors
  
• New brake lines
• New brass sleeves/caliper bolts (1 set per caliper).
• Rags or kitty litter to soak up spilled brake fluid
• Pan to drain brake fluid into
  

Notes about Applications, Brake Pads, Rotors, and Fluids:

16" Wheels on the IROC/IROC R/T
The calipers and pads used for the IROC & IROC R/T series Daytonas with 16" wheels appear to be identical to those cars with 15" wheels.  This is not obvious as most part sites don't list 16" wheels as an option on these cars.  The original calipers on Mike's IROC exactly matched the replacements from AutoZone spected for cars with the 15" wheels.

Brake Fluid
When you start looking into doing your first brake job, you may be confused by the problem of what kind of brake fluid you should be using.  You'll see DOT 3, DOT 4, DOT 5, and DOT 5.1 advertised.  These are US Department of Transporation standards for minimum brake fluid properties.

Our cars came from the factory with DOT 3 fluid.  You can replace it with either DOT 3, DOT 4, or DOT 5.1.  Any residual fluid in the lines won't hurt anything here because all are made of "poly glycol ethers".  Don't worry, no knowledge of chemistry is required.  In general though, you should avoid mixing brands or old & new fluids when you fill up though.. 

All poly glycol ether fluids are termed as "hydroscopic" which means they quickly absorb moisture from the air.  "Wet" brake fluid boils at a much lower temperature and the resulting vapor is very compressible meaning that your brake pedal will get spongy and not work well.  Thus don't use brake fluid that's been sitting around for awhile.  Different brands of fluid offer different formulations that may be more or less resistant to moisture absorpsion but all are still hydroscopic to some degree.

DOT 5 fluid is a silicone based oil.  It isn't hydroscopic but instead separates like water and oil.  In this case, any water sitting in the caliper will cause corrosion and boil at 212º F giving you even worse braking.  This stuff also can't be mixed with the poly glycol ether kind of fluid and is twice as compressible which makes for a softer/spongier pedal feel.  In general, silicone brake fluids should just be avoided.

Below are the US Department of Transportatoin minimum standards for each rating of brake fluid.  DOT2 is listed for comparison but is obsolete by today's standards.

Designation	Dry Boiling Point	Boiling Point @ 3% Moisture
DOT 2	374ºF	-
DOT 3	401ºF	284º F
DOT 4	446º F	311º F
DOT 5	500º F	356º F
DOT 5.1	518º F	375º F

Don't fret too much over what you use (brand, natural, synthetic, rating).  As long as the fluid is DOT 3 or DOT 4 compliant it will work just fine for a street car.   There are also fluids made for racing with higher boiling points, but for most of us, DOT 4 is just fine.

As an example of what's out there, in case someone is still fretting over what to buy, Mike is currently using "Valvoline SynPower DOT 3 & 4 Brake Fluid" in his IROC.  It seems to be working great and was readily available at PepBoys for a very reasonable price.  According to the MSDS, it's rated at 503º F dry and 343º F wet.  (This isn't intended as an advertisement or an endorsement, but is just one example of a product that you could use.  MANY others exist, some rated higher, some rated lower.)

For more information on brake fluids, see the following off site links:

http://www.shotimes.com/SHO3brakefluid.html
http://www.stoptech.com/whitepapers/brakefluidcomparison.htm
http://www.stealth316.com/2-brakefluid.htm

Brake Pads

Although there is certainly more to brake pads than can be listed here, below are the genral categories in which brake pad materials fall.  Each manufacturer uses different combinations of materials so the overall properties of a brake pad will vary by brand and model.

Ceramic Pads - Ceramic pads produce less brake dust than other pads so you will have less to clean off of your wheels.  They are also quiet and last a long time.  These are the most modern type of brake pad you can get and offer excellent performance.  Most car manufactuers are now using ceramic pads on the vehicles they turn out.  Ceramics tend to be better than semi-metallics in lower temperature environments that a typical driver encounters.  All though these pads are very good, they are generally not recommended for towing and heavy applications.

Semi-Metallic Pads - Semi-metallic pads are made up of a a combination of organic materials and metals. They offer great performance and last longer than ordinary organic pads.   Semi-metallics may require time to come up to an optimal temperature range for peak breaking efficiency and are thus suited to extreme conditions like towing and racing.  Semi-metallics are also harsher on rotors than the organic and ceramic varieties.

Organic Pads - Organic materials are used in base level pads and were used in many older vehicles. These materials are softer and wear out faster than the other types of pads.  They also suffer more from brake fade.

When buying brake pads, keep in mind that you can't have everything.  There is no such thing as a quiet brake pad that offers superior performance, no brake dust, a no rotor wear, a solid pedal, and a lifetime warrany.  If you want to stop as fast as possible, there will be wear to the pads and rotors.  That's just how it works.  Different materials are good for different heat ranges and driving habits.  Thus, you should do some comparison shopping before making a decision on what to buy.  The descriptions listed above are only generalizations to guide you. 

For more on brake pads, see the following off site links:

http://www.partsamerica.com/ChoosingBrakePads.asp
http://www.tirerack.com/brakes/tech/perf_categories.html
http://www.minimania.com/MM/BRAKES___Pad_types___choices_936.htm
http://www.shotimes.com/brakes/survey/brakes3.html

Brake Rotors

Brake rotors come with a few different options to be aware of.

Vented vs. Solid Discs - Some of our cars came with solid discs, others came with the vented variety.  "Vented" dics have openings in the middle of the disc with vanes supporting the outer surfaces.  These openings or vents are designed to reduce heat build up in the rotor and help prevent warping.

Cross Drilled Rotors - Cross drilling provides added cooling to the rotor for improved stopping performance.  It also looks cool but will reduce the life of your brake pads (think cheese grater) and may shorten the effective life of the rotor itself.  Drilling rotors that were not intended to be cross drilled can lead to cracking and rotor failur

Slotted Rotors - Slotting of a rotor allows it to bite harder into the brake pad for the ultimate stopping performance on heavy vehicles or for race or autocross.  Slotted rotors will perform well but will also eat through brake pads more quickly. 


Parking Brake Shoes

Parking brake shoes do not seem to be a commonly sold part at least from the perspective of internet searches.  At the time of this writing, Autozone, Parts America, Rock Auto, and Auto Parts Giant do not list parking brake shoes among their offerings.  Napa did.

The shoes (at least the ones from Napa) come in a set of 4, 2 shoes per side.  So when you ask for shoes you don't need to ask for 2 sets.

Mike was refused his core $14 charge because one of the shoes was missing the pad.  Apparently when they are worn down to the metal, the remanufacturers don't want them. In reality, Mike's weren't worn down to the metal per se...  the pad shattered off the metal.  In any case, this is something to keep in mind if you're are getting thin.