00-05-22-002N

File in Section:
Bulletin No.:
Service Bulletin
Date:
05 - Brakes
00-05-22-002N
June, 2013
WARRANTY ADMINISTRATION
Subject:
Disc Brake Warranty Service and Procedures
Models:
2014 and Prior GM Passenger Cars and Light Duty Trucks
EXCLUDING 2009-2013 Chevrolet Corvette ZR1 and Z06 Equipped with RPO Z07
This bulletin is being revised to add the 2013-2014 model years and update the labor
operation and Warranty Information. Please discard Corporate Bulletin
Number 00-05-22-002M (Section 05 – Brakes).
For your convenience, this bulletin updates and
centralizes all GM's Standard Brake Service
Procedures and Policy Guidelines for brake rotor and
brake pad service and wear. For additional information,
the Service Technical College lists a complete index of
available Brake courses. This information can be
accessed at www.centerlearning.com > resources >
training materials > brakes courseware index. In
Canada, refer to Service Know How course 55040.00V
and Hydraulic Brake Certification program 15003.16H.
Important: PLEASE FAMILIARIZE YOURSELF WITH
THESE UPDATES BEFORE PERFORMING YOUR
NEXT GM BRAKE SERVICE.
Copyright 2013 General Motors LLC. All Rights Reserved.
The following four (4) key steps are a summary of
this bulletin and are REQUIRED in completing a
successful brake service.
1. Measure and Document Pre-Service
Rotor Thickness* (REQUIRED on Repair
Order) – determine rotor clean-up/refinish/
replace
2. Properly clean ALL brake corner mating
surfaces – hub, rotor and wheel
3. Properly clean-up/refinish rotor, measure and
document post-service rotor thickness
(REQUIRED on Repair Order)
Important: If it is determined the rotor needs to be
refinished, verify lathe equipment is properly calibrated.
4. Properly reassemble the brake corner using
proper torque tools, torque specification and
torque sequence — wheel lug nuts.
* The bulletin refers to Minimum Thickness
specification as the minimum allowable thickness after
refinish. Always refer to SI to verify the spec stamped
on the rotor is the minimum thickness spec after
refinish and not the discard spec.
Page 2
June, 2013
Bulletin No.: 00-05-22-002N
Bulletin Format
Bulletin Topic
Repair Order Required Documentation
— Rotor Original and Refinished Thickness
— Explanation of Part Replacement
GM Brake Service Procedure
— Brake Service Procedure
— Bench Type Lathe
— On-Car Type Lathe
— Hubless Rotor
— Hubbed/Captured/Trapped Rotor
Brake Lathe Calibration Procedure
— Bench-Type Lathe
— On-Car Type Lathe
Brake Pulsation
Brake Rotor Clean-Up Procedure
Brake Noise
Key Points – Frequently Asked Questions
Brake Warranty
Tool Information
Correction Plate Part Information
Warranty Information
Worksheet – Brake Lathe Calibration
Form: GM Brake Service Repair Order Documentation for Required Measurements
***REPAIR ORDER REQUIRED
DOCUMENTATION
Important: When using any one of the brake
labor operations listed in this bulletin (except for
2480018 — Brake Burnish), the following two rotor
measurements (1. Original Rotor Thickness,
2. Refinished Rotor Thickness are required and MUST
be written/documented on the repair order, or for your
convenience, complete the form (GM Brake Service
Repair Order Documentation for Required
Measurements) found on the last page of this bulletin
and attach it to the repair order. If the Warranty Parts
Center generates a request, this Documentation/Form
must be attached to the repair order that is sent back.
Important: Documentation of brake lathe
maintenance and calibration as recommended by the
lathe manufacturer must be available for review upon
request.
Repair Order Documentation — Rotor Original And
Refinished Thickness — REQUIRED
When resurfacing a brake rotor or drum, the ORIGINAL
thickness (measured thickness before refinish) and
REFINISHED thickness (measured thickness after
refinish) MUST be written/documented on the repair
order hard copy for each rotor serviced. If a rotor
replacement is necessary, only the original thickness
measurement needs to be recorded.
Repair Order Documentation — Explanation of Part
Replacement — REQUIRED
If replacement of a brake component is necessary,
proper documentation on the repair order is required.
See the following examples:
• Brake rotor replacement — Customer comment
was brake pulsation. Rotor was refinished on a
prior brake service. After rotor measurement, it
was determined that refinishing the rotor again
would take it under the Minimum Thickness
specification.
• Brake pad replacement — Customer comment
was brake squeak noise. On inspection, found
pads contaminated by fluid leak at caliper.
GM BRAKE SERVICE PROCEDURE
Brake Service Procedure
1. Remove the wheel and caliper.
2. Measure rotor thickness. In order to determine if
the rotor can be refinished, do the following steps:
Important: If performing routine Brake Service for
worn pads only, and the rotors are not damaged and
measure within specification – DO NOT REFINISH
ROTORS.
2.1. Remove the rotor(s).
Bulletin No.: 00-05-22-002N
June, 2013
2.2. Measure the rotor for original thickness using
a brake micrometer. Multiple measure points
should be taken and the lowest measurement
should be recorded.
2.3. Reference the Minimum Thickness
specification stamped on the backside of the
rotor or SI for Minimum Thickness
specification/other. In most cases, the rotor
should be refinished unless the measurement
taken makes it obvious that refinishing the
rotor would take the measurement under the
Minimum Thickness specification (then
replacement is necessary). DO NOT use any
other manufacturers rotor specifications.
3. ***Record the lowest ORIGINAL rotor thickness
measurement on the repair order hard copy as
noted in the “Repair Order Documentation — Rotor
Refinish” section of this bulletin.
4. Clean all of the mating surfaces between
the hub, the rotor and the wheel using the
J 42450A – Wheel Hub Cleaning Kit and
J 41013 – Whiz Wheel®.
If rotors are not to be refinished – Go To Step 8.
Important: Cleaning all mating surfaces and making
them free of corrosion, burrs and other debris (which
includes removal of Hubless rotors) is critical and
MUST be performed whether using an On-Car or
Bench Lathe Refinish Procedure.
5. Be sure to follow the appropriate refinishing
procedure listed below for the type of lathe you
are using.
Important: Only replace the rotors if they do not meet
the Minimum Thickness specification.
Important: DO NOT REFINISH NEW ROTORS.
Important: Only remove the necessary amount of
material from each side of the rotor and note that equal
amounts of material do not have to be removed from
both sides on any brake system using a floating caliper.
Important: Prior to making the cut, install the
recommended clip-on style disc silencer supplied with
the lathe. Use of this silencer is critical to prevent
chatter from occurring during the cut.
Bench Type Lathe
5.1. Refinish the existing rotor on an approved,
well-maintained lathe to guarantee smooth,
flat and parallel surfaces.
5.2. Check for clean and true lathe adapters and
make sure the arbor shoulder is clean and
free of debris or burrs. For more information,
see the “Brake Lathe Calibration Procedure
(Bench-Type)” section in this bulletin.
5.3. On the outboard area of the rotor, position the
cutting tools one eighth of an inch into the
brake pad area of the rotor. Feed the cutting
tools into the rotor until they cut the rotor to
new metal, a full 360 degrees. Zero each dial
and back off a full turn
5.4. Move the cutting bits to the middle of the rotor
and do the same procedure. If zero is passed
during the process, reset zero. Back off a
full turn.
Page 3
5.5. Position the cutting bits one eighth of an inch
inside the inboard (closest to the hub) edge of
the brake pad contact area. Do the same
procedure. If zero is passed during the
process, reset zero.
5.6. Back off a full turn and position the cutting bits
all the way inboard in preparation to refinish
the full rotor surface. Advance both tool
cutters to the zero setting plus just enough to
clean up the entire rotor surface.
5.7. After completing the refinish, sand both sides
of the rotor for approximately one minute per
side using a sanding block and 130–150 grit
sandpaper to obtain a non-directional finish.
On-Car Type Lathe
5.1. Reinstall the rotor(s).
Important: When using the On-Car lathe on vehicles
equipped with limited slip (or posi-trac) rear system, it is
critical that the rear drive shaft is disconnected/
disengaged prior to operation of the On-Car lathe.
Remember to mark and re-index the drive shaft
correctly on re-assembly to prevent creating driveline
vibration. Whenever the lathe drive motor is being
switched on, the operator MUST keep their body out of
the wheel well area until the machine has reached its
normal operating RPM.
5.2. Refinish the existing rotor on an approved,
well-maintained lathe to guarantee smooth,
flat and parallel surfaces.
Important: When raising the vehicle on the lift, be
sure to have it at a good working height (waist high is
average) to accommodate mounting the On-Car lathe.
Optimally, the center piston on the lathe trolley will be
mid-travel. If the lathe trolley center piston is completely
compressed (bottoming out) or inversely fully extended
and hanging off the vehicle hub, this could affect the
calibration time of the lathe.
5.3. Select the correct adapter for the vehicle
you're working on and mount it to the hub with
the vehicle lug nuts. Hand tighten 34-41 Y
(25-30 lb ft) the nuts using equal torque. DO
NOT use impact wrenches, excessive torque
will damage the adapter.
Important: Ensure the adapter sits flush on the rotor
hat surface. Be sure to remove any rust, rotor retaining
clips, etc. that may preclude the adapter from sitting flat
on the mounting surface.
5.4. Connect the lathe to the adapter, turn on the
lathe and activate the computer to
compensate for run-out in the hub.
5.5. Once the computer indicates the
compensation process was successful, on the
outboard area of the rotor, position the cutting
tools one eighth of an inch into the brake pad
area of the rotor. Feed the cutting tools into
the rotor until they cut the rotor to new metal,
a full 360 degrees. Zero each dial and back
off a full turn.
5.6. Move the cutting bits to the middle of the rotor
and do the same procedure. If zero is passed
during the process, reset zero. Back off a
full turn.
Page 4
June, 2013
5.7. Position the cutting bits one eighth of an inch
inside the inboard (closest to the hub) edge of
the brake pad contact area. Do the same
procedure. If zero is passed during the
process, reset zero.
5.8. Back off a full turn and position the cutting bits
all the way inboard in preparation to refinish
the full rotor surface. Advance both tool
cutters to the zero setting plus just enough to
clean up the entire rotor surface.
5.9. After completing the refinish, sand both sides
of the rotor for approximately one minute per
side using a sanding block and 130-150 grit
sandpaper to obtain a non-directional finish.
5.10. Dismount the lathe, but leave the lathe
adapter attached to the vehicle.
6. Once the rotor has been properly machined, wash
the rotor with soap and water (use a mild dish
washing soap) or wipe it clean with GM approved
brake cleaner, P/N 88862650 (Canadian
P/N 88901247).
Important: Thoroughly cleaning the rotor will prevent
the possible transfer of finite metal dust left as a
by-product of machining to the pad material during the
seating process, thus reducing the opportunity for
squeaks or other noises to occur.
7. ***Record the REFINISHED rotor thickness
measurement on the repair order hard copy. Refer
to the “Repair Order Documentation — Rotor
Refinish” section of this bulletin.
8. Setting up to measure for Lateral Run Out (LRO):
Important: Measuring for Lateral Run Out (LRO)
(steps 8-15) is no longer required however, these steps
are being left in the overall procedure as a good check
to be performed in the case of a repeat pulsation
complaint. If you are not checking for LRO, go to
step 16.
Bench-Type Lathe
8.1. Ensure that the mating surfaces of the rotor
hat section and the hub mating surface are
clean and free of debris.
8.2. Mount the new, original or refinished rotor
onto the vehicle hub.
Important: Always hold the rotor on the bottom half so
any debris that may be dislodged from the vents will fall
out instead of falling into the mounting area. Any
movement or jarring from the rotor falling over on the
studs can release rust from the vents on the rotor.
8.3. Tilt the top of the rotor in towards the vehicle
so you can see the studs and ease the rotor
onto the studs.
8.4. Slide the rotor all the way to the hub and hold
it in place until you have placed one of the
conical washers (with the tapered hole side
facing out) and run the first lug nut up tight by
hand so the rotor doesn't move when you
release it.
Bulletin No.: 00-05-22-002N
8.5. Place the conical washers on the rest of the
studs (with the tapered hole side facing out),
start and snug the lug nuts by hand.
8.6. Using the one half inch drive impact wrench
and a torque stick (J-39544) or equivalent,
start with the lug nut opposite of the one you
first tightened by hand and tighten the lug
nuts using a star pattern until they touch the
hub but do not completely torque. Then again,
starting with the first lug nut you tightened by
hand, tighten all the lug nuts in a star pattern
to the specific vehicle torque specification.
8.7. DO NOT reinstall the caliper or the wheel at
this time.
On-Car Type Lathe
8.1. Leave the On-Car adapter on the wheel.
8.2. Proceed to Step 9.
9. Fasten the dial indicator to the steering knuckle so
that the indicator needle contacts the rotor
outboard friction surface approximately 6.35 mm
(0.25 in) from the rotor's outer edge. The stylus
should be perpendicular to the friction surface of
the rotor.
Important: Make sure the dial indicator needle tip is
screwed tight, a loose tip could cause false readings.
10. Measure for LRO. Follow the procedure below to
determine if the LRO is within specification
(0.050 mm (0.002 in) or LESS).
10.1. Rotate the rotor and locate the point on the
rotor where the lowest dial indicator reading
is indicated and set the dial indicator to zero.
10.2. Rotate the rotor from the low point and
locate the point with the highest dial
indicator reading (rotor “high spot”). Note the
amount and mark the location of the “high
spot” on the rotor and mark the closest
wheel stud relative to this location. If the
high point falls between two studs, mark
both studs. In instances where the vehicle
has “capped lug nuts” you should mark
the hub.
11. If the Lateral Run Out (LRO) measurement is
0.050 mm (0.002 in) or LESS, no correction is
necessary. Go to Step 15 if this is the first rotor
completed. Go to Step 16 if this is the second rotor
completed. If the LRO is GREATER than 0.050 mm
(0.002 in), go to Step 12.
12. If the LRO measurement is greater than 0.050 mm
(0.002 in), use the following procedure to correct
for LRO:
Important: If the LRO measurement is over 0.279 mm
(0.011 in), determine the source or cause of the LRO
and correct it (i.e. verify drive axle nut torque
specification, refinished rotor is source of LRO due to a
lathe qualification issue – see “Brake Lathe Calibration
Procedure”).
Bulletin No.: 00-05-22-002N
June, 2013
Hubless Rotor
12.1. Remove the rotor and using the Brake
Align® application chart (found in the
latest version of Corporate Bulletin
Number 01-05-23-001) , choose the correct
plate to bring the rotor LRO to 0.050 mm
(0.002 in) or less. The plates come in
0.0762 mm (0.003 in), 0.1524 mm (0.006 in)
and 0.2286 (0.009 in) compensation. For
more information on proper plate selection,
see the instruction video/DVD included in
the “Brake Align®” kit or the latest
version of Corporate Bulletin
Number 01-05-23-001.
12.2. Align the V-notch of the selected Brake
Align® correction plate to the marked wheel
stud (“high spot”) or between the two points
marked (if the “high spot” is between two
wheel studs).
Important: IF Brake Align® Correction Plates are not
available for the vehicle being serviced, refer to SI
Document — Brake Rotor Assembled Lateral Runout
Correction for correcting LRO.
Important: Per Brake Align® manufacturer, NEVER
attempt to stack two or more Correction Plates together
on one hub. NEVER attempt to reuse a previously
installed Correction Plate.
12.3. Reinstall the rotor using the same method
and precautions as the first time – found in
Step 8. Make sure to index the rotor correctly
to the marks made in step 10, otherwise
LRO will be comprised.
Hubbed / Captured / Trapped Rotor
12.1. Measure the rotor thickness.
12.2. Refinish or replace the rotor (see Service
Information for further details).
13. Use a Dial Indicator to measure the rotor to verify
the LRO is within specification.
14. If using,
BENCH LATHE — DO NOT remove conical
washers and lug nuts at this time.
ON—CAR LATHE — You must remove adapter
and install conical washers and lug nuts to retain
rotor position.
Important: For Hubless rotor design, while removing
the adapter, you must hold the rotor tight to the hub and
install the top conical washer and lug nut first to ensure
no debris falls between the surface while removing the
adapter. Then, install the remaining conical washers
and lug nuts. Otherwise, LRO will be comprised.
15. Perform Steps 1 through 7 on the opposite side of
the vehicle (steps 1-12, if performing LRO).
16. Reinstall the rotors on both sides of the vehicle and
perform the following steps:
16.1. Reinstall the calipers and pads.
16.2. Pump the brakes to pressurize the calipers.
16.3. Remove the lug nuts/conical washers.
16.4. Install and properly torque the wheels.
Page 5
Important: It is critical to follow the star pattern wheel
torque procedure and use the proper tools (torque stick
or torque wrench) as referenced in SI.
17. Road test the vehicle to verify the repairs.
BRAKE LATHE CALIBRATION
PROCEDURE
Calibration of the brake lathe should be performed
and recorded monthly or whenever post-service
brake rotor LRO measurements are consistently
reading above specification.
BENCH-TYPE LATHE
Use the following procedure to calibrate a Bench-type
brake lathe:
1. After refinishing a rotor, loosen the arbor nut and
while holding the inside bell clamp to keep it from
rotating, rotate the rotor 180 degrees.
2. Retighten the arbor nut and set the dial indicator on
the rotor using the same instructions as checking
the run out on the vehicle.
3. Rotate the arbor and read the runout.
4. Divide the reading by two and this will give you the
amount of runout the lathe is cutting into the rotor.
Important: If there is any runout, you will need to
machine the inside bell clamp in place on the lathe (this
procedure is for a Bench type lathe ONLY, DO NOT
machine inside the bell clamp on an On-Car type lathe).
Machining the Inside Bell Clamp (Bench Type
Lathe Only)
Any nicks or burrs on the shoulder of the arbor must be
removed. An 80-grit stone can be used to accomplish
this. Spray WD-40® on the shoulder and with the lathe
running, hold the stone flat against the shoulder surface
using slight pressure. When the burrs are gone, clean
the surface. Burrs must also be removed from the hub
of the inside bell clamp. This can be accomplished with
the stone and WD-40®. Keep the stone flat on the hub
while removing the burrs. After removing the burrs,
clean the hub.
Place the bell clamp on the arbor of the lathe and use
the small radius adapters first and then spacers to allow
you to tighten the arbor nut to secure the bell clamp to
the lathe. Position the tool bit in the left hand of the rotor
truer so you can machine the face of the bell clamp.
Machine the face of the bell clamp taking just enough
off of it to cut the full face of the clamp the full
360 degrees. Before you loosen the arbor nut, match
mark the hub of the bell clamp to the arbor and line up
these marks before machining a rotor. A magic marker
can be used to make the match marks. Machine a rotor
and recheck the calibration. Repeat this procedure on
all Inside Bell Clamps used.
Important: If runout is still present, contact the brake
lathe supplier.
Page 6
June, 2013
ON-CAR TYPE LATHE
Use the following procedure to calibrate an On-Car
brake lathe:
1. Connect the lathe to a vehicle using the
appropriate adapter.
2. Attach a vise-grip dial indicator to a fixed point in
the wheel well and bring the dial indicator to a flat
surface on the cutting head.
3. Turn on the lathe and press the “start” button so
the lathe begins to compensate.
4. Once compensation is complete, note the runout
as measured by the dial indicator. Measured
runout at this point is overstated given that it is
outside the rotor diameter.
5. If runout is in excess of 0.1016 mm (0.004 in)
(0.050 mm (0.002 in) as measured within the rotor
diameter), calibration must be tightened. Follow
manufacturer's instructions for tightening the
calibration of the lathe. This information is found in
the manual supplied with the lathe.
Important: If the machine is taking a long time to
compensate during normal use, prior to checking the
lathe calibration, it is recommended that the machine
be disconnected from the adapter and the adapter (still
connected to the vehicle) is rotated 180 degrees and
the machine reattached. This will accomplish two
things:
- It will re-verify the machine is properly attached to the
adapter.
- It will change the location of the runout (phase)
relative to the machine and thus possibly allow for quick
compensation as a result of the position change.
The following information has been added as a
reference to ensure your Pro-Cut PFM lathe provides a
consistent smooth surface finish over long term usage.
Cutting Tips / Depth of Cut / Tip Life
The cutting tips must be right side up. Reference marks
always face up. The cutting tips may not have chips or
dings in the surface of the points. Cuts of
0.1016-0.381 mm (0.004-0.015 in) will provide the best
surface finish and the optimal tip life. When cleaning or
rotating the cutting bits, make sure that the seat area
for the tip on the tool is free and clear of debris.
Cutting Head
On each brake job, the technician must center the
cutting head for that particular vehicle using one of the
mounting bolt holes on the slide plate. Once the head is
centered, it is vital that the technician use one hand to
push the head firmly and squarely back into the dovetail
on the slide plate while using the other hand to tighten
the Allen-Hex bolt that secures the head. Failure to do
this could result in chatter occurring during the cut.
Tool Holder Plate (Cutting Head)
The tool holder plate is the plate that the cutting arms
are attached to. It can bend or break if a technician
accidently runs the cutting arms into the hub of the rotor
while the rotor is turning. (Cuts of more than 0.508 mm
(0.020 in) can also bend this plate). Once bent, the
lathe will most likely not cut properly until the tool holder
plate is replaced. In order to verify the condition of the
Bulletin No.: 00-05-22-002N
tool holder plate on a machine that will not cut right,
remove the mounting bolt and remove the cutting head
from the slide plate. With the cutting head titled at an
angle, lay the long edge of the tool holder plate down
on the flat part of the slide plate. If any gap can be seen
between the edge and the slide plate, the tool holder
plate is bent and the source of vibration. Also check to
ensure that the cutting arms are lying flat on the upper
side of the tool holder plate. If the mounting arm post is
bent, it will show itself by having the back of the cutting
arm lifting off the surface of the tool holder.
Gib Adjustment / Loose Gib
As wear occurs between the slide plate and the box it
rides on, you must take up the slack. You do this by
way of a moveable wedge, which we call the gib. Your
lathe manual details adjustment process, which you
should perform when required after monthly checks or
whenever surface finish is inconsistent.
BRAKE PULSATION
Brake pulsation is caused by brake rotor thickness
variation. Brake rotor thickness variation causes the
piston in the brake caliper, when applied, to “pump” in
and out of the caliper housing. The “pumping” effect is
transmitted hydraulically to the brake pedal. Brake
pulsation concerns may result from two basic
conditions:
1. Thickness Variation Pulsation is Caused by Lateral
Run Out (LRO). LRO on a brake corner assembly
is virtually undetectable unless measured (with a
dial indicator after the brake service) and will
not be detected as brake pulsation during an
after brake service test drive. If the brake corner
is assembled with excessive LRO (greater than
0.050 mm (0.002 in), thickness variation will
develop on the brake rotor over time and miles.
Excessive LRO will cause the brake pads to wear
the brake rotors unevenly, which causes rotor
thickness variation. Pulsation that is the result of
excessive Lateral Run Out usually develops in
4,800-16,000 km (3,000-10,000 mi). The more
excessive the LRO, the faster the pulsation will
develop. LRO can also be induced when uneven
torque is applied to wheel nuts (lug nuts). Improper
wheel tightening after tire rotation, spare tire
usage, brake inspection, etc. can be the cause of
brake pulsation. Again, it usually takes
4,800-16,000 km (3,000-10,000 mi) AFTER the
service event for the condition to develop. The
customer does not usually make the connection
between the service event and the awareness of
the pulsation. The proper usage of torque
wrenches (torque limiting sockets) will greatly
reduce or eliminate the pulsation conditions after
wheel service events. The improper use of impact
wrenches on wheel nuts greatly increases the
likelihood of pulsation after wheel service.
Bulletin No.: 00-05-22-002N
June, 2013
The following are examples of pulsation conditions
and reimbursement recommendations:
• If the customer noticed the condition between
4,800-16,000 km (3,000-10,000 mi) and it
gradually got worse, normally the repair would
be covered. The customer may tolerate the
condition until it becomes very apparent.
– If a GM dealer performed a prior brake
service, consider paying for the repair and
then strongly reinforce proper brake lathe
maintenance.
– If the customer had the brake service done
outside of a GM dealership, normally GM
would not offer any assistance.
• If a customer indicated they had wheel service,
ask who performed the service. Then;
– If a GM dealer performed the service,
consider paying for the repair and then
strongly reinforce the use of torque wrenches
at the dealer. Two common size torque
wrenches cover 90% of all GM products.
Each technician needs to use torque
wrenches properly every time the wheel nuts
are tightened.
– If the customer had the wheel service done
outside of a GM dealership, normally GM
would not offer any assistance.
2. Thickness Variation Pulsation Caused by Brake
Rotor Corrosion — Rotor corrosion is another form
of thickness variation, which can cause a pulsation
concern and can be addressed as follows:
• Cosmetic Corrosion:
In most instances rotor corrosion is cosmetic
and refinishing the rotor is unnecessary.
• Corrosion — Pulsation Caused by
Thickness Variation (Lot Rot / Low
Miles — 0–321 km (0–200 mi):
At times more extensive corrosion can cause
pulsation due to thickness variation. This
usually happens when the vehicle is parked for
long periods of time in humid type conditions
and the braking surface area under the pads
corrodes at a different rate compared to the rest
of the braking surface area. Cleaning up of
braking surfaces (burnishing) can be
accomplished by 10 – 15 moderate stops from
56– 64 km/h (35 – 40 mph) with cooling time
between stops. If multiple moderate braking
stops do not correct this condition, follow the
“Brake Rotor Clean-Up Procedure” below.
• Corrosion — Pulsation Caused by
Thickness Variation (without rotor flaking /
higher mileage — 3,200-8,000 km
(2,000-5,000 mi):
In some cases, more extensive corrosion that is
not cleaned up by the brake pad over time and
miles can cause the same type of pulsation
complaint due to thickness variation. In these
cases, the rotor surface is usually darker
instead of shiny and a brake pad foot print can
be seen against the darker surface. This darker
surface is usually due to build-up, on the rotor
Page 7
material surface, caused by a combination of
corrosion, pad material and heat. To correct this
condition, follow the “Brake Rotor Clean-up
Procedure” below.
• Corrosion — Pulsation Caused by
Thickness Variation (with rotor flaking /
higher mileage — 8,000 + km
(5,000 + miles) :
At times, more extensive corrosion over time
and miles can cause pulsation due to thickness
variation (flaking). This flaking is usually a build
up, mostly on the rotor material surface, caused
by a combination of corrosion, pad material and
heat. When rotor measurements are taken, the
low areas are usually close to the original rotor
thickness (new rotor) measurement and the
high areas usually measure more than the
original rotor thickness (new rotor)
measurement (depending on mileage and
normal wear). To correct this condition, follow
the “Brake Rotor Clean-up Procedure”
described below.
Important: In some flaking instances, cleaning-up this
type of corrosion may require more rotor material to be
removed then desired. Customer consideration should
be taken in these situations and handled on a case by
case basis, depending on the amount/percentage of
rotor life remaining and the vehicle's warranty time and
miles.
BRAKE ROTOR CLEAN-UP
PROCEDURE
Clean-up the rotors on an approved, well-maintained
brake lathe to guarantee smooth, flat and parallel
surfaces. Check for clean and true lathe adapters and
make sure the arbor shoulder is clean and free of
debris or burrs. For more information see the “Brake
Lathe Calibration Procedure” section in this bulletin.
1. On the outboard area of the rotor, position the
cutting tools one eighth of an inch into the brake
pad area of the rotor. Feed the cutting tools into the
rotor until they cut the rotor to new metal, a full
360 degrees. Zero each dial and back off a
full turn.
2. Move the cutting bits to the middle of the rotor and
do the same procedure. If zero is passed during
the process, reset zero. Back off a full turn.
3. Position the cutting bits one eighth of an inch
inside the inboard (closest to the hub) edge of the
brake pad contact area. Do the same procedure. If
zero is passed during the process, reset zero.
4. Back off a full turn and position the cutting bits all
the way inboard in preparation to refinish the full
rotor surface. Advance both tool cutters to the zero
setting plus just enough to clean up the entire rotor
surface.
5. After completing the refinish, sand both sides of
the rotor for approximately one minute per side
using a sanding block and 130-150 grit sandpaper
to obtain a non-directional finish.
Page 8
June, 2013
Important: Only remove the necessary amount of
material from each side of the rotor and note that equal
amounts of material do not have to be removed from
both sides on any brake system using a floating caliper.
Important: In many of these instances, such a
minimal amount of material is removed from the rotor
that customer satisfaction is not a concern for future
brake services. This procedure is intended to
“Clean-up” the rotor surface and should be conveyed to
the customer as such – not as “cut”, “refinish” or
“machine”, which tends to be terms understood as a
substantial reduction of rotor material/life. If the brake
lathe equipment being used is not capable of removing
minor amounts of material while holding tolerances,
further lathe maintenance, repair, updates or equipment
replacement may be necessary.
KEY POINTS — FREQUENTLY ASKED
QUESTIONS
•
•
BRAKE NOISE
Some brake noise is normal and differences in loading,
type of driving, or driving style can make a difference in
brake wear on the same make and model. Depending
on weather conditions, driving patterns and the local
environment, brake noise may become more or less
apparent. Verify all metal-to-metal contact areas
between pads, pad guides, caliper and knuckles are
clean and lubricated with a thin layer of high
temperature silicone grease. Brake noise is caused by
a “slip-stick” vibration of brake components. While
intermittent brake noise may be normal, performing 3 to
4 aggressive stops may temporarily reduce or eliminate
most brake squeal. If the noise persists and is
consistently occurring, a brake dampening compound
may be applied to the back of each pad. This allows
parts to slide freely and not vibrate when moving
relative to each other. Use Silicone Brake Lubricant,
ACDelco P/N 88862182 (Canadian P/N 88862496) or
equivalent.
The following noises are characteristics of all braking
systems and are unavoidable. They may not indicate
improper operation of the brake system.
•
•
Squeak/Squeal Noise:
• Occurs with front semi-metallic brake pads at
medium speeds when light to medium pressure is
applied to the brake pedal.
• Occasionally a noise may occur on rear brakes
during the first few stops or with cold brakes and/
or high humidity.
Grinding Noise:
• Common to rear brakes and some front disc
brakes during initial stops after the vehicle has
been parked overnight.
• Caused by corrosion on the metal surfaces during
vehicle non-use. Usually disappears after a few
stops.
Groan Noise:
A groan type noise may be heard when stopping
quickly or moving forward slowly from a complete stop.
This is normal. On vehicles equipped with ABS, a groan
or moan type noise during hard braking applications or
loose gravel, wet or icy road conditions is a normal
function of the ABS activation.
Bulletin No.: 00-05-22-002N
•
•
Q: How do on-car lathes react to Axle Float? Does
the play affect the machining of the rotor, either
surface finish or LRO?
A: Because the Pro-Cut on-car lathe adjusts in a
live mode while spinning the hub/rotor, the
dynamics of a floating axle are effectively
eliminated. Once the lathe is compensated, there
is no difference in the cutting/surface finish and
LRO are just the same as with a non-floating axle.
Q: Which lathe is essential for performing brake
work, the bench or on-car?
A: Dealers must have a well maintained bench
lathe and well maintained on-car lathe. These
lathes need to be calibrated on a monthly basis.
BOTH lathes are essential to providing quality
brake service.
Q: What is the expected tip life for an on-car
lathe?
A: The geometry and composition of the Pro-Cut
tips are designed for “single pass” cutting. When
using the Pro-Cut the cutting depth should be set
to take all material needed to get below rust
grooves, eliminate all run-out and resurface the
entire disc in a single pass. Cuts of
0.1016-0.381 mm (0.004-0.015 in) will provide the
best surface finish and the optimal tip life. No
“skim cut” or “finish cut” is needed. Failure to
follow this procedure will shorten tip life. The
Pro-cut tips will last between 7-12 cuts per corner.
With three usable corners, a pair of tips is good for
at least 21 cuts.
Q: Why does GM recommend the use of single
pass (referred to as “positive rake”) bench and
on-car brake lathes?
A: GM Service and GM Brake Engineering have
performed competitive evaluations on a significant
number of bench and on-car brake lathes.
These tests measured critical performance
characteristics such as flatness, surface finish and
the ability of the lathe to repeat accuracy over
many uses. In each test, single pass lathe designs
out performed the competitors. Single pass brake
lathes are more productive requiring less time to
perform the same procedure.
Q: Is it okay to leave the caliper/pads installed
while cutting rotors using an on-car lathe?
A: On-car lathes should never be used with the
pads and calipers installed on the vehicle. The
debris from cutting the rotors can contaminate the
brake pads/calipers which can lead to other brake
concerns and comebacks.
Q: What information needs to be documented on
the Repair Order?
A: Any claim that is submitted using the labor
operations in this bulletin, must have the Original
Rotor Thickness and Refinish Rotor Thickness (if
refinished) documented on the repair order. For
more information, refer to the “Repair Order
Required Documentation” section of this bulletin.
Bulletin No.: 00-05-22-002N
June, 2013
All Warranty Repair Orders paid by GM, are
subject to review for compliance and may be
debited where the repair does not comply with this
procedure.
BRAKE WARRANTY
Brake Rotors:
• Brake rotor warranty is covered under the terms of
the GM New Vehicle Limited Warranty. Reference
the vehicle's warranty guide for verification.
• Rotors should not be refinished or replaced during
normal/routine pad replacement.
• Rotors should not be refinished or replaced and is
ineffective in correcting brake squeal type noises
and/or premature lining wear out.
• Rotors should not be refinished or replaced for
cosmetic corrosion. Clean up of braking surfaces
can be accomplished by 10–15 moderate stops
from 56-64 km/h (35-40 mph) with cooling time
between stops.
• Rotors should not be refinished or replaced for
rotor discoloration/hard spots.
• Rotors should be refinished NOT replaced for
Customer Pulsation concerns. This condition is a
result of rotor thickness variation, usually caused
by LRO (wear induced over time and miles) or
corrosion (Lot Rot).
• When rotor refinishing, only remove the necessary
amount of material from each side of the rotor and
note that equal amounts of material do not have to
be removed from both sides on any brake system
using a floating caliper.
• Rotors should be refinished for severe
scoring — depth in excess of 1.5 mm (0.060 in).
Important: If the scoring depth is more than 1.5 mm
(0.060 in) after the rotor is refinished, it should be
replaced.
• It is not necessary to replace rotors in pairs.
Rotors may be replaced individually. However,
caution should be exercised, as a variance in
surface finish may cause a brake pull condition.
• New rotors should not be refinished before
installation. Original equipment rotor surfaces are
ground to ensure smooth finish and parallelism
between mounting and friction surfaces. If a new
rotor has more than 0.050 mm (0.002 in) Lateral
Run Out (LRO) when properly mounted on the
hub, correct it using one of the following methods:
10.1. For hubless rotor designs, use the
correction plate procedure found in the “GM
Brake Service Procedure for Hubless
Rotors” outlined in this bulletin.
10.2. For hubbed/trapped/captured rotor designs,
refinish the rotor using an On-Car lathe and
the procedure outlined in this bulletin.
• Never reuse rotors that measure under the
Minimum Thickness specification. In this instance,
the rotor should be replaced.
Page 9
Important: If the Minimum Thickness specification is
not visible on the rotor, reference Service Information
(SI) for the specific vehicle application. DO NOT use
any other manufacturers rotor specifications.
Brake Pads:
Important: When determining the warranty coverage
(as an example) – if all four front or four rear brake pads
are excessively worn evenly, that would NOT be
covered under warranty since this type of wear is most
likely due to driving habits or trailering. However, if the
brake pads are excessively worn un-evenly,
side-to-side or same side/inner-to-outer pads, then
consideration should be given to cover this under
warranty since this type of wear is most likely due to
poor operation of other braking components.
• Consideration should be given for covering brake
pads up to 39,000 km (24,000 mi) (excluding
owner abuse, excessive trailering, or the
situations that would not be considered
normal use).
• Installation of new rotors does not require pad
replacement. Do not replace pads unless their
condition requires it – excessively worn, damage
or contaminated.
Brake Wear:
Several factors impact brake lining wear and should be
taken into account when reviewing related issues:
- heavy loads / high temperatures / towing /
mountainous driving / city driving / aggressive driving /
driver braking characteristics (left foot or two feet)
The following are conditions that may extend brake
lining wear:
- light loads / highway driving / conservative driving /
level terrain
TOOL INFORMATION
Tool Description
Tool Number
Brake Rotor Micrometer —
English
J 45021
Brake Rotor Micrometer —
Metric
J 44279
Wheel Hub Cleaning Kit
J 42450A
Whiz Wheel
®
J 41013
Torque Stick
J 39544 Kit
Dial Indicator Kit
(.001 Increments)
J 45101
Conical Washers
J 45101–100
Page 10
June, 2013
CORRECTION PLATE PART
INFORMATION
Correction Plate
Correction Plate — 0.0762 mm (0.003 in)
Correction Plate — 0.1524 mm (0.006 in)
Correction Plate — 0.2286 mm (0.009 in)
Refer to Corporate Bulletin Number 01-05-23-001 for
the Brake Align® application chart.
For vehicles repaired under warranty, Brake Align ®
Run-Out Correction Plates should be submitted in the
Net Amount at cost plus 40%. Brake Align ® Run-Out
Correction Plates are available through the following
suppliers:
• Dealer Equipment and Services
at 1-800-GM TOOLS
• Brake Align® LLC at 1-888-447-1872
(U.S. Dealers Only)
* We believe this source and their products to be
reliable. There may be additional manufacturers of
such products. General Motors does not endorse,
indicate any preference for or assume any
responsibility for the products from this firm or for any
such items, which may be available from other sources.
•
If correcting for LRO, claim the use of correction
plates as OLH. The times for using correction
plates are not to exceed 0.2 hr for one side and
0.4 hr for both sides. Guidelines for submitting
OLH per General Motors Policy & Procedures
should be followed.
• Model years 2005 to current — labor
operations 2420670, 2420671 and 2420760,
2420761, are to be used only when replacing
rotors.
• Model years 2005 to current — labor
operations 2420672, 2420762, 2430032 and
2430052 have been established for Brake Rotor/
Drum Refinishing.
• For model years in which the new labor operations
do not apply, the time for refinishing the rotor is in
labor operations 2420670, 2420671 and 2420760,
2420761.
For vehicles repaired under warranty, use:
Labor
Operation
Description
Labor Time
2480018*
Brake Burnish
0.3 hr
2420150
Pads, Front Disc Brake –
Replace
2420170
Pads, Disc Brake-Rear –
R&R or Replace
2420670
Rotor Asm-Front
Replacement
2420671
Rotor Asm-Front Both –
Replace
2420760
Rotor Asm-Rear R&R or
Replacement
2420761
Rotor Asm-Rear Both –
Replace
2420672
Brake Rotor Refinishing
– Front
2420762
Brake Rotor Refinishing
– Rear
2430032
Brake Drum Refinishing
– Front
2430052
Brake Drum Refinishing
– Rear
WARRANTY INFORMATION
Important:
• Labor operation 2480018 — Brake Burnish is not
a published labor operation and will not be found
in the Labor Time Guide. This labor operation
should be used to claim the necessary time for
cleaning up the braking surfaces for thickness
variation pulsation due to “lot rot” corrosion – refer
to Brake Pulsation section of this bulletin for
procedure. Thickness Variation Pulsation due to
“lot rot” corrosion occurs when vehicles are not
driven for an extended period of time. This type of
corrosion clean-up is covered under the terms of
the new vehicle warranty coverage.
Bulletin No.: 00-05-22-002N
Use Published
Labor
Operation Time
*This is a unique labor operation for bulletin use only. It will
not be published in the Labor Time Guide.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
WE SUPPORT VOLUNTARY
TECHNICIAN
CERTIFICATION
Bulletin No.: 00-05-22-002N
June, 2013
WORKSHEET — BRAKE LATHE CALIBRATION
Important: Brake lathe calibration should be
performed and recorded monthly or if you are
consistently measuring high LRO after rotor refinishing.
BRAKE LATHE CALIBRATION CHECK SHEET
Dealer Code: _________________________
Date: _________________________
Lathe Type: ______________________________
Lathe Model:____________________________
What is the Lathe's Run Out?______________________
Is the Lathe within Specification? __________ Yes
Comments:
__________ No
Page 11
Page 12
June, 2013
Bulletin No.: 00-05-22-002N
ATTACHMENT FORM — GM BRAKE SERVICE REPAIR ORDER DOCUMENTATION
FOR REQUIRED MEASUREMENTS
PART MEASUREMENT/REPLACEMENT DOCUMENTATION
Dealer Code: _________________________
Repair Order Number: _________________________
Front Rotor - ORIGINAL/REFINISHED thickness measurements (required when front labor operation is used):
• Thickness Specification (Min. Thickness/Discard Stamped on Rotor/SI): ____________________ inch/mm (Circle One)
• ORIGINAL measured thickness before refinish: Left Front (OLF)__________ inch/mm Right Front (ORF)__________
inch/mm
• REFINISHED measured thickness after refinish: Left Front (RLF)__________ inch/mm Right Front (RRF)__________
inch/mm
Rear Rotor - ORIGINAL/REFINISHED thickness measurements (required when rear labor operation is used):
• Thickness Specification (Min. Thickness/Discard Stamped on Rotor/SI): ____________________ inch/mm (Circle One)
• ORIGINAL measured thickness before refinish: Left Rear (OLR)__________ inch/mm
Right Rear (ORR)__________ inch/mm
• REFINISHED measured thickness after refinish: Left Rear (RLR)__________ inch/mm
Right Rear (RRR)__________ inch/mm
Rotor Replacement:
If rotors are replaced, you must indicate reason for replacement
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________
Pad Replacement:
If Pads are replaced, you must indicate reason for replacement:
_________________________________________________________________________________________________
_________________________________________________________________________________________________
_________________________________________________________________________________________________