File in Section:

Service Bulletin

Bulletin No.:
Date:

06 - Engine
10-06-01-008L
November, 2014

TECHNICAL
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:

2007-2014 Cadillac Escalade Models
2007-2013 Chevrolet Avalanche, Silverado
2007-2014 Chevrolet Suburban, Tahoe
2010-2012 Chevrolet Colorado
2010-2015 Chevrolet Camaro
2007-2013 GMC Sierra, Sierra Denali
2007-2014 GMC Yukon Models
2010-2012 GMC Canyon
2008-2009 Pontiac G8 GT
Vehicles Built Prior to February 1, 2011 Require Updated Valve Cover and October 2010
Require AFM Shield
Equipped with Any of the Following Engines:
– Aluminum Block V8 Engine with Active Fuel Management (AFM) (RPOs LH9, L94,
LZ1, L99, LC9, LH6, L76, L92, LFA (Hybrid))
– Iron Block V8 Engine with Active Fuel Management (AFM) (RPOs LMG, LY5)

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 has been revised to update the Models and Warranty Information. Please
discard Corporate Bulletin Number 10-06-01-008K.

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.

Correction
Note: When installing the updated valve cover or reinstalling a used valve cover, verify that the baffles can hold
water and do not leak. If any leaks are found, seal with RTV if possible or replace the valve cover. Thoroughly clean
and dry the valve cover before installation.

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
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

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 28 Y (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.

Cast-Iron Block - Oil Getting Past Piston Rings - Free Up Piston Rings on All Models
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.

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.
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 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
(2009-2014 Truck Models Only)

1

12570427

COVER ASM-VLV RKR ARM
(2007-2008 Truck Model Only)

1

12642655

COVER ASM-VLV RKR ARM
(2010-2015 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 (2010-2015 Camaro)

1

19300410

Piston and Ring Service Kit
(2007-2009 5.3L Only)

1

19300411

Piston and Ring Service Kit
(2010-2014 5.3L Only)

1

Warranty Information
For vehicles repaired under the Powertrain coverage, use the following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH) for coverage information.
Labor
Operation

4080298*

4066891

Description

Labor
Time

Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (Camaro Only)

6.5 hrs

Clean Carbon from Cylinder
and Install Rocker Arm Cover Left Bank

2.6 hrs

Install AFM Oil Deflector,
Rocker Arm Cover- Left Bank
and Clean Carbon from
Cylinder (2WD)

4.1 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

Piston, Connecting Rod, and
Bearing Replacement - Both
Sides

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.