Cleanoh4

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Aug 27, 2013
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This was brought up in another thread, so I thought I'd take the initiative and start it. Post up common TSB's and maybe it will become a one stop resource for common issues. Use complete TSB's only.

I'll start with a few:

G80 and Additive

LOCKING DIFFERENTIAL LUBRICANT (SERVICE INFORMATION) #91-4-109
SUBJECT: LOCKING DIFFERENTIAL (G80) LUBRICANT - (SERVICE INFORMATION)
VEHICLES AFFECTED: ALL LIGHT TRUCKS EQUIPPED WITH G80 REAR AXLE ALL YEARS
Some light duty trucks equipped with locking rear axles (G80) may exhibit rear axle chatter, especially when turning a corner from a stop.
This condition of alternate engagement and disengagement of clutches in differential assembly is usually caused by contaminated axle lubricant.
To correct this condition, drain and refill the rear axle with SAE 80W-90 GL5 (P/N 10950849).

The use of any additive in locking rear axles (G80) is not recommended. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. All light duty trucks equipped with RPO G80 make use of a locking differential and the use of additives will delay the engagement of the locking mechanism and may decrease axle life.

VEHICLES/COMPONENTS INVOLVED: ------------------------- ---- Some light duty trucks equipped with locking rear axles, RPO G80.
SERVICE PARTS INFORMATION:
Part Number Description ----------- ------------------ 10950849 Lubricant, Rear Axle (1 litre)
Parts are currently available through CANSPO.
WARRANTY INFORMATION:
As specified in Light Duty Truck Maintenance Schedules, locking rear axle fluid drain and refill is required owner maintenance at the first engine oil change. Failure to drain and refill the rear axle as specified may contribute to a later axle chatter condition. Refer to the appropriate Light Duty Truck Maintenance Schedule or service manual, section OB, for further details on change intervals.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those 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 a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
© Copyright General Motors Corporation. All Rights Reserved.
 

Cleanoh4

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Body Mount Insulator
#06-08-61-003D: Underbody Pop or Clunk Type Noise While Turning or Driving on Uneven Road Surfaces (Install Body Mount Insulator) - (Sep 10, 2008)
Subject: Underbody Pop or Clunk Type Noise While Turning or Driving on Uneven Road Surfaces (Install Body Mount Insulator)

Models: 2004-2008 Cadillac Escalade, Escalade ESV, Escalade EXT
2004-2008 Chevrolet Avalanche, Suburban, Tahoe
2004-2008 Chevrolet Silverado (Classic), Silverado
2004-2008 GMC Yukon, Yukon XL, Yukon Denali, Yukon Denali XL
2004-2008 GMC Sierra (Classic), Sierra Denali (Classic), Sierra, Sierra Denali



This bulletin is being revised to update the model years and include diagnosis information. Warranty information has also been updated. Please discard Corporate Bulletin Number 06-08-61-003C (Section 08 - Body and Accessories).

Condition

Some customers may comment on a pop or clunk type noise while turning or driving on uneven road surfaces. This noise can be heard and/or felt at either the driver's or front passenger floor pan area.

Cause

Under certain conditions, normal movement between the frame and the #1, #2 or #3 body mounts may cause this noise to occur.
Diagnosis

1. If the vehicle is equipped with aftermarket (non-GM Accessory) running boards or the running board is mounted using the body mount bolt, remove the running boards prior to test driving the vehicle. This will eliminate the running boards as the possible cause of the noise.
2. Install the J-39570 Chassis Ears to the frame rail at or near the body mounts.
3. Test drive the vehicle to identify which mount is suspect.

Correction

Install an insulator at the suspect mount(s). The insulator should be installed between the upper portion of the body mount and the frame bracket. The #1 mount is the mount located just under the A-pillar. The #2 mount is the mount located just under the B-pillar. The #3 mount is the mount located just under the C-pillar. Use the procedure listed below.

INSULATOR PART NUMBER 15899719

1. Raise the vehicle on the hoist. It is recommended to use a four-post lift or strap the vehicle frame to the hoist arms.
2. For the left side mounts only, remove the intermediate park brake cable. Perform the following steps:
2.1. Remove the nut from the park brake equalizer.
2.2. Remove the intermediate cable from the equalizer.
2.3. Depress the retaining tabs that secure the park brake cable to the frame.
2.4. Pull slightly on the cable from the mounting area in order to provide slack for body movement without binding the cable.
3. Remove all of the body mount bolts on the side being repaired.
4. Properly support the body at the body mount area.
Caution: When you remove the body mount, do NOT separate the frame from the body more than is necessary. Possible personal injury and damage to multiple parts may result.
5. Lower the chassis accordingly in order to remove the upper portion of the body mount.
6. Install the new insulator to the bottom of the top portion of the body mount. The picture shows the insulator (1) location after the body mount is reassembled.
7. Install the body mount to the frame bracket.
8. Perform the following procedure before installing the bolts.
8.1. Clean the bolt threads of all the original thread locking compound.
8.2. Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry.
8.3. Apply Threadlocker, GM P/N 89021297 (In Canada, use P/N 10953488).
9. Install the body mount bolts.

Tighten
For 2003, 2004 and 2005 model year, tighten the bolts to 85 N·m (63 lb ft).

Tighten
For 2006-2008 model year, tighten the bolts to 100 N·m (74 lb ft).
10. Reinstall the intermediate park brake cable (left side only).
 

Cleanoh4

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ABS Low Speed Activation

Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface) #03-05-25-007 - (09/29/2003)


Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface)
2002-2004 Cadillac Escalade, Escalade EXT

2003-2004 Cadillac Escalade ESV

1999-2004 Chevrolet Silverado

2001-2004 Chevrolet Suburban, Tahoe

2002-2004 Chevrolet Avalanche

2003-2004 Chevrolet Express

1999-2004 GMC Sierra

2001-2004 GMC Yukon, Yukon XL

2003-2004 GMC Savana

2003-2004 HUMMER H2

Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph). Upon investigation, the technician will find no DTCs set.

Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the hub reluctor ring due to rust and debris built up on the sensor mounting surface.

Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.

Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General Information sub-section of the Service Manual (SI Document ID #899664).
Disconnect both the front wheel speed sensor (WSS) connectors at the frame and harness.
Place a Digital Volt Meter (DVM) across the terminals of each WSS connector.
Rotate the wheel clockwise approximately one revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual. Plug the WSS bore in order to prevent debris from falling into the hub during service.
Clean the WSS mounting surface on the hub to remove any rust or corrosion using a wire brush, or equivalent.

Important
Make sure that the sensor sits flat on the hub. Check the sensor flange against a straight edge to ensure flatness. If the sensor flange is distorted, replace the sensor.


Apply a thin layer of bearing grease to the hub surface and sensor O-ring prior to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344.
Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush against the hub. Refer to the applicable Wheel Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel. The voltage should now read at least 350 ACmV's.
 

Cleanoh4

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Blower Motor Resistor

10240 - SPECIAL COVERAGE ADJUSTMENT - HEATING, VENTILATION, AND AIR CONDITIONING BLOWER NOT FULLY FUNCTIONAL OR INOPERATIVE
SERVICE CAMPAIGN BULLETIN
Reference Number(s): 10240, Date of Issue: May 09, 2011 2003-2006 Chevrolet Avalanche, Suburban Tahoe; 2003-2007 Chevrolet Silverado; 2003-2006 GMC Yukon, Yukon XL; 2003-2007 GMC Sierra; Equipped with Manual HVAC (CJ3) or Heavy Duty Heater (C42) Affected Model(s):
Related Ref Number(s): 10240
ARTICLE BEGINNING
CONDITION
On some 2003-2006 model year Chevrolet Avalanche, Suburban, Tahoe; GMC Yukon, Yukon XL; and 2003-2007 model year Chevrolet Silverado and GMC Sierra vehicles equipped with a manual heating, ventilation, and air conditioning (HVAC) system (CJ3) or heavy duty heater (C42), the interface between the electrical terminals of the relay resistor module and the wiring connector that powers the module may be incapable of conducting higher current levels for sustained periods of blower motor operation. In addition, moisture and other contaminants may enter the fresh air intake plenum and contact the internal circuit of the module or corrode the terminals. If any of these were to occur, the relay resistor module or wiring connector could overheat and the HVAC blower may not function on certain blower settings or may be inoperative. This may be accompanied by a burning smell or smoke.
SPECIAL POLICY COVERAGE ADJUSTMENT
This special coverage covers the condition described above for a period of 10 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership.
Dealers are to install a new blower motor resistor and resistor module connector. The repairs will be made at no charge to the customer.
For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after May 10, 2011, are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair orders prior to May 10, 2011, must be submitted to the Service Contract provider.
VEHICLES INVOLVED
Involved are certain 2003-2006 model year Chevrolet Avalanche, Suburban, Tahoe; GMC Yukon, Yukon XL; and 2003-2007 model year Chevrolet Silverado and GMC Sierra vehicles equipped with a manual HVAC (CJ3) or heavy duty heater (C42).
IMPORTANT: Dealers are to confirm vehicle eligibility prior to beginning repairs by using the Applicable Warranties section in the Global Warranty
Management system.
PARTS INFORMATION
Parts required to complete this special coverage are to be obtained from General Motors Customer Care and Aftersales (GMCC & A).
Parts Information Part Number Description Qty/ Vehicle 15862656 Connector, SW-Pwr St Adjr 1 89019088 Resistor, Blo Mot (A/C & Htr) 1 89019089 Resistor, Blo Mot (Heater Only) 1
SERVICE PROCEDURE
NOTE: The resistor module connector and blower motor resistor will need to be replaced if one or more of the symptoms below is present.
 The HVAC blower may not function on certain or all blower speed settings
 A burning plastic smell or smoke may be present in the vehicle
 The HVAC blower may run continually with the ignition in the OFF position

Determine if one or more of the above symptoms is present. If required, refer to HVAC diagnostic information in SI. Refer to Resistor Module Connector and Blower Motor Resistor Replacement in this bulletin if one or more of the symptoms are present. Other HVAC repairs are NOT covered in this product safety special coverage bulletin.
Resistor Module Connector and Blower Motor Resistor Replacement
1.Remove the blower fuses (Htr A/C & HVAC 1 fuses). 2.Lower the close-out panel enough to gain access to the resistor module connector. 3.Disconnect the connector from the resistor module.
NOTE: Connector replacement is required even if the connector was replaced on a previous service repair.
4.Remove the tape from the wiring harness to expose the wiring.
5.Cut the wires back far enough from the connector to eliminate any melted insulation on the wire.
NOTE: Use the old connector as a map for splicing the wires for the new connector. Be sure to use the correct crimping tool from the terminal repair kit J 38125. Use only Duraseal splice sleeves. Other splice sleeves may not protect the splice from moisture or provide a good electrical connection.
6.Install the new connector. Use the yellow splice sleeves provided with the connector. 7.Install the new blower motor resistor. 8.Reinstall the fuses. Test the blower motor to make sure all speeds are functional. 9.Reinstall the hush panel/close-out panel.
CUSTOMER REIMBURSEMENT
Customer requests for reimbursement of previously paid repairs for the condition described in this bulletin are to be submitted to the dealer May 31, 2012, unless otherwise specified by State law. Repairs must have occurred within 10 years of the date the vehicle was originally placed in service, or 150,000 miles (240,000 km), whichever occurs first.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be reimbursed will be limited to the amount the repair would have cost if completed by an authorized General Motors dealer.
When a customer requests reimbursement, they must provide the following:
 A completed Customer Reimbursement Request Form. This form is mailed to the customer or can be obtained from the dealer.
 The name and address of the person who paid for the repair.
 VIN, original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a description of the repair, and the person or entity performing the repair.
FOR US DEALERS:
If a reimbursement request is denied, dealers MUST provide the customer with an explanation, in writing, as to why the request was denied. GM expects all reimbursement requests to be properly resolved within 30 days of receipt. If the denial was due to missing documents, the customer can resubmit when the missing documents are obtained, as long as it is still within the allowed reimbursement period.
COURTESY TRANSPORTATION - FOR US
The General Motors Courtesy Transportation program is intended to minimize customer inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited Warranties. The availability of courtesy transportation to customers whose vehicles are within the warranty coverage period and involved in a product program is very important in maintaining customer satisfaction. Dealers are to ensure that these customers understand that shuttle service or some other form of courtesy transportation is available and will be provided at no charge. Dealers should refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation guidelines.
WARRANTY TRANSACTION INFORMATION
Submit a transaction using the table below.
Warranty Transaction Information Labor Code Description Labor Time Net Item T5816 Diagnostic Time Only - No Repair Required (condition other than described in bulletin) 0.1-0.3 N/A T5817 Replace HVAC Module Connector and Resistor 0.6 N/A T5818 Customer Reimbursement Approved 0.2 * T5819 Customer Reimbursement Denied - For US dealers only 0.1 N/A
* The amount identified in "Net Item" should represent the dollar amount reimbursed to the customer.
CUSTOMER NOTIFICATION
General Motors will notify customers of this special coverage on their vehicles (see copy of typical customer letter included with this bulletin - actual divisional letter may vary slightly).
OWNER LETTER
Dear General Motors Customer:

**removed apology section due to posting size limitations-(we love you, we're sorry, we're doing the right thing) you get the drift**

Customer Notification Division Number Text Telephones (TTY) Chevrolet 1-800-222-1020 1-800-833-2438 GMC 1-800-462-8782 1-888-889-2438 Guam 65-6267-1752 Puerto Rico - English 1-800-496-9992 Puerto Rico - Espanol 1-800-496-9993 Virgin Islands 1-800-496-9994
We are sorry for any inconvenience you may experience; however we have taken this action in the interest of your continued satisfaction with our products.
Jim Moloney
General Director,
Customer and Relationship Services
Enclosure
10240
 

Tylers88

3 GM's and a Jeep
Apr 16, 2012
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Clarion, IA
Wasn't there a tsb on the early GMT800s for low speed surging, like creeping in a parking lot, because of spark plug gap being set at 0.060" when it should have been 0.040"? I know this is probably corrected on 99% of them already but they do still say 0.060" under the hood IIRC.
 

Cleanoh4

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Subject: Engine Oil Consumption on Aluminum Block/Iron Block Engines with Active Fuel
Management (AFM) (Install AFM Oil Deflector and Clean Carbon from Cylinder and/or
Install Updated Valve Cover)
Models: 2007-2011 Cadillac Escalade Models
2007-2011 Chevrolet Avalanche, Silverado 1500, Suburban, Tahoe
2010-2011 Chevrolet Camaro
2007-2011 GMC Sierra 1500, Sierra Denali, Yukon Models
2008-2009 Pontiac G8 GT
Built Prior to February 1, 2011 (Updated Valve Cover) and October 2010 (AFM Shield)
Equipped with Any of the Following Engines:
– Aluminum Block V8 Engine with Active Fuel Management (AFM)
(RPOs L94, LZ1, L99, LC9, LH6, L76, LFA, L92)
– Iron Block V8 Engine with Active Fuel Management (AFM) (RPOs LMG, LY5)
– Hybrid Engine (RPO LFA – Only Applies to Hybrid Models Built July 7, 2009 -
February 1, 2011 – Prior Builds Not Cast For AFM Valve)
Attention: This bulletin does not apply to the Buick Rainier, Chevrolet TrailBlazer and GMC Envoy
equipped with LH6 due to a different design oil pan and AFM pressure relief valve.
This bulletin is being revised to update the Warranty Information. Please discard Corporate
Bulletin Number 10-06-01-008F (Section 06 – Engine/Propulsion System).
Condition
Some customers may comment about engine oil
consumption of vehicles with higher mileage
(approximately 48,000 to 64,000 km (30,000 to
40,000 mi) and a service engine soon light being on
and/or rough running engine. Verify that the PCV
system is functioning properly. If the customer
understands that some oil consumption is normal and
still feels the consumption level is excessive, more than
1 quart per 2000 to 3000 miles of driving, perform the
service indicated in this bulletin. It is no longer
necessary to have the customer return multiple times to
have the usage verified.
Cause
This condition may be caused by two conditions. Oil
pulled through the PCV system or oil spray that is
discharged from the AFM pressure relief valve within
the crankcase. Under most driving conditions and drive
cycles, the discharged oil does not cause a problem.
Under certain drive cycles (extended high engine
speed operation), in combination with parts at the high
end of their tolerance specification, the oil spray
quantity may be more than usual, resulting in excessive
deposit formation in the piston ring grooves, causing
increased oil consumption and cracked or fouled spark
plugs (#1 and/or #7). Refer to the latest version of
Corporate Bulletin Number 12-06-01-001.
Page 2 January, 2013 Bulletin No.: 10-06-01-008G
Correction
Aluminum or Cast Iron Block - Oil in Intake
Manifold - Install Updated Valve Cover on All
Models Built Prior to February 1, 2011
Note: If vehicle is built after this breakpoint, it should
already be equipped with this updated valve cover.
2740641
1) Old Design
2) New Design
PCV pullover or an overactive lifter can cause oil to be
pulled through the PCV system even at low vehicle
mileage. A correctly functioning PCV system will only
leave a film of oil in the intake manifold. Inspect the
intake manifold to see if there is any oil puddling in the
bottom. If there is you will need to replace the left valve
cover. Two new left rocker arm covers have been
released for trucks and vans. Technicians should
replace the left rocker arm cover with GM
P/N 12570427 for 2007-2008 or GM P/N 12642655 for
2009-2011. Refer to the Parts Information below for the
Camaro. This rocker arm cover has a relocated PCV
drain hole that prevents oil from entering the intake
manifold. Refer to Valve Rocker Arm Cover
Replacement - Left Side in SI.
Note: These rocker covers are for specific years. The
PCV orifice is different for each. The correct cover must
be used or an SES light may set.
Aluminum Block - Oil Getting Past Piston
Rings - Free Up Piston Rings and Install AFM
Shield on All Non-Hybrid Models Built Prior to
October 1, 2010 or all Hybrid Models Built
July 7, 2009 - October 1, 2010
Note: If vehicle is built outside of this breakpoint, it
should already be equipped with this AFM shield
or the pan does not have an AFM valve (LFA before
July 7, 2009).
To correct this condition, install an AFM shield, perform
the piston cleaning procedure as described in this
document and install a new oil pan gasket per the
procedure outlined in this document. Monitor oil
consumption after this repair to ensure oil consumption
has improved to acceptable levels.
If this repair does not correct the condition, it may be
necessary to replace all of the piston assemblies
(piston and rings) with new parts. Refer to SI for repair
procedure.
Important: It is critical in this cleaning process that the
engine/fuel injector cleaner remain in the cylinders for a
minimum of 2.5 hours to fully clean the components.
The cleaner solution must be removed before a
maximum of three hours.
1. Remove the spark plugs and ensure that none of
the pistons are at top dead center (TDC).
2. Clean the pistons by putting 118-147 ml (4-5 oz) of
Upper Engine and Fuel Injector Cleaner, GM
P/N 88861803 (in Canada, use 88861804), in each
cylinder. Allow the material to soak for at least
2.5-3.0 hours, but no more than three hours and
then remove the cleaner. A suggested method of
removing the cleaner is cranking the engine over.
Make sure to unplug the ignition coils and fuel
injector before cranking the engine over. Also
make sure that the painted surfaces are covered
so no damage is done.
3. Remove the oil pan. Refer to Oil Pan Replacement
in SI.
2474205
Bulletin No.: 10-06-01-008G January, 2013 Page 3
4. Remove the AFM valve (1).
2474207
5. Install the new shield (1), GM P/N 12639759, and
tighten the AFM valve to the oil pan to 28Y
(20 lb ft).
Important: Ensure that the engine cleaner is
thoroughly removed before reinstalling the spark plugs.
Failure to do so may result in a hydro-lock condition.
6. Reinstall the spark plugs. Replace the spark plugs
if necessary due to full of carbon. Refer to the parts
catalog.
7. Reinstall the oil pan. Refer to the Oil Pan
Installation procedure in SI. Replace the oil pan
gasket if necessary. Refer to the parts catalog.
Replace the engine oil.
8. Re-evaluate the oil consumption. Document on the
repair order. If the oil consumption is still greater
than 0.946 L (1 qt) in 3,200 km (2000 mi),
replacement of the pistons and rings will be
required.
Important: Some minor scratches may be noticed on
the cylinder walls during piston and ring replacement. If
the scratch cannot be felt when running your finger nail
over it, the scratch is considered normal wear and the
block or engine should not be replaced.
Note: It is not necessary to hone or deglaze the
cylinder walls. Honing may induce unnecessary
cylinder wall and / or piston ring damage if it is done
incorrectly and/or not cleaned thoroughly. Cylinder
walls should cleaned thoroughly with brake cleaner
before installation of the new pistons and rings.
Numerous engines replaced for oil consumption have
been inspected. The cross hatch has been consistently
good and is in specification. As a result, is should not
be necessary to measure the cylinders if they pass the
visual inspection.
Note: After the piston/ring replacement it will take
2000-3000 mi. for the new rings to seat. Adequate
break time is necessary prior to rechecking the oil
consumption level.
Note: Do not overlook the valve seals at higher
mileage. Look in the head ports for evidence of
excessive amounts of oil getting past the seals.
Note: It is recommended to install an AFM shield any
time that the oil pan is removed for any reason and an
AFM shield is not found.

- - - - - - - - - -auto merged double post- - - - - - - - - -

Cast-Iron Block - Oil Getting Past Piston
Rings - Free Up Piston Rings on All Models
Built Prior to October 1, 2010
1. Remove the spark plugs and ensure that none of
the pistons are at top dead center (TDC).
2. Clean the pistons by putting 118-147 ml (4-5 oz) of
Upper Engine and Fuel Injector Cleaner, GM
P/N 88861803 (in Canada, use 88861804), in each
cylinder. Allow the material to soak for at least
2.5-3.0 hours, but no more than three hours and
then remove the cleaner. A suggested method of
removing the cleaner is cranking the engine over.
Make sure to unplug the ignition coils and fuel
injector before cranking the engine over. Also
make sure that the painted surfaces are covered
so no damage is done.
Important: Ensure that the engine cleaner is
thoroughly removed before reinstalling the spark plugs.
Failure to do so may result in a hydro-lock condition.
3. Reinstall the spark plugs. Replace the spark plugs
if necessary due to full of carbon. Refer to the parts
catalog.
4. Re-evaluate the oil consumption. Document on the
repair order. If the oil consumption is still greater
than 0.946 L (1 qt) in 3,200 km (2000 mi),
replacement of the pistons and rings will be
required.
Note: It is not necessary to install the shield when
doing the piston cleaning on a cast iron block engine
since the cast iron block engine uses a different oil
pump than an aluminum block engine, which results in
a higher engine speed before the AFM pressure relief
valve opens (cast iron block engines are less prone to
the AFM oil spray condition described earlier). If you
find it necessary to replace the pistons and/or remove
the oil pan for any other reason, only then should you
add the shield.

- - - - - - - - - -auto merged double post- - - - - - - - - -

Page 4 January, 2013 Bulletin No.: 10-06-01-008G
2596639
2596640
Important: Some minor scratches may be noticed on
the cylinder walls during piston and ring replacement. If
the scratch cannot be felt when running your finger nail
over it, the scratch is considered normal wear and the
block or engine should not be replaced.

- - - - - - - - - -auto merged double post- - - - - - - - - -

cylinder walls. Honing may induce unnecessary
cylinder wall and / or piston ring damage if it is done
incorrectly and/or not cleaned thoroughly.
 

Cleanoh4

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Aug 27, 2013
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Cylinder
walls should cleaned thoroughly with brake cleaner
before installation of the new pistons and rings.
Numerous engines replaced for oil consumption have
been inspected. The cross hatch has been consistently
good and is in specification. As a result, is should not
be necessary to measure the cylinders if they pass the
visual inspection.
Note: After the piston/ring replacement, it will take
2000-3000 miles for the new rings to seat. Adequate
break time is necessary prior to rechecking the oil
consumption level.
Note: Do not overlook the valve seals at higher
mileage. Look in the head ports for evidence of
excessive amounts of oil getting past the seals.
Note: It is recommended to install an AFM shield any
time that the oil pan is removed for any reason and an
AFM shield is not found.
Parts Information
Part Number Description Qty
12639759 DEFLECTOR-OIL PRESS RLF
VLV (quantity of 3 per order) 1
88861803 (in
Canada, use
88861804)
CLEANER, F/INJR 16 OZ LIQUID
POUR (Upper Engine and Fuel
Injector Cleaner)
3
12612350 GASKET, OIL PAN 1
12642655 COVER ASM-VLV RKR ARM
(2009-2011 Truck Models Only) 1
12570427 COVER ASM-VLV RKR ARM
(2007-2008 Truck Model Only) 1
12642655 COVER ASM-VLV RKR ARM
(2010-2011 Camaro) 1
12570427
COVER ASM-VLV RKR ARM
(2008–2009 G8 WITHOUT
RPO BSI Only)
1
12642655 COVER ASM-VLV RKR ARM
( 2009 G8 WITH RPO BSI Only) 1
12610768 PCV Tube (2010-2011 Camaro) 1
Bulletin No.: 10-06-01-008G January, 2013 Page 5
Warranty Information
For vehicles repaired under the U.S. (5 years/
100,000 miles) or Canadian (5 years/160,000 km)
Powertrain Warranty, use:
Labor
Operation Description
Labor
Time
J7555*
Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (Camaro Only)
6.5 hrs
Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (Aluminum Block V8)
(RPOs L94, LZ1, L99, LC9,
LH6, L76, LFA, L92)
4.1 hrs
Clean Carbon from Cylinder
and Install Rocker Arm Cover -
Left Bank (Cast Iron Block V8)
(RPOs LMG, LY5)
2.6 hrs
Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (4WD)
5.2 hrs
Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (G8 Only)
5.7 hrs
*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.
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