File in Section:
Bulletin No.:

Service Bulletin

Date:

06 - Engine
13-06-01-003C
September, 2013

TECHNICAL
Subject:

Excessive Oil Consumption – Perform Oil Consumption Test and/or Install Piston and
Piston Ring Kit

Models:

2010-2013 Buick LaCrosse
2011-2013 Buick Regal
2010-2013 Chevrolet Equinox
2010-2013 GMC Terrain
Equipped with 2.4L Engine (RPOs LAF, LEA)
This bulletin has been revised to update the Warranty Information. Please discard
Corporate Bulletin Number 13-06-01-003B.

Condition
Some customers may comment on excessive oil
consumption and/or that they have to add oil between
oil changes.

Correction
For this condition, technicians should perform an oil
consumption test by following the latest version of
Corporate Bulletin Number 01-06-01-011. Before
starting the oil consumption test, verify the ECM has
latest TIS2web calibrations to adjust the engine oil life
monitor to a maximum of 7,500 miles (12,070 km) —
Refer to Customer Satisfaction Bulletin #12312.
Inspect for any obvious oil leaks that may explain the oil
consumption concern and repair as necessary.
Important: When checking the oil level with the oil
dipstick design shown below, please note that the oil
volume per notch is not linear due to the shape of the
block. The upper notches (relative to the top of the
handle) equal 0.24 quart (0.227 L) between each notch
while the lower notches only equal 0.14 quart (0.132 L)
between each notch. As a result, no oil will appear on
the dipstick if it is low on oil by approximately
1.25 quarts (1.18 L) or more. When determining the oil
consumption rate, the oil volume added to return it to
the starting location is the total amount of oil consumed.
The consumption rate must be documented on a repair
order.
Notice: Do not add too much oil. An overfill can lead to
burn off of the excess oil. Advise the customer to wait
until the oil is below the cross-hatched area at the tip of
the dipstick before adding oil.

Copyright 2013 General Motors LLC. All Rights Reserved.

3339530

If the oil consumption test indicates that the rate of
consumption is greater than 1 quart (0.946 L) of oil
every 2,000 miles (3,200 km), note the oil consumption
rate, the date that the ECM was reprogrammed and any
repairs/diagnosis that you have performed.
The repair is to replace the pistons and rings. In some
cases the bore surface may not have a uniform look to
the finish (zebra stripes) as shown below. As a result,
some technicians may question whether the engine
should be repaired or replaced. After careful evaluation,
GM Powertrain has determined that the new pistons
and rings will perform correctly in bores that have this
appearance so engine replacement should not be
necessary. The cylinder bores do not need any
machine or honing work performed on them. Refer to
the picture below for acceptable surface finishes.

Page 2

September, 2013

Important: DO NOT use any abrasive wheels/
materials to clean any mating surfaces. Only Plastic
scrapers should be used. Please refer to the latest
version of Corporate Bulletin Number 00-06-01-012.

Bulletin No.: 13-06-01-003C

Note: Returned oil consumption engines have been
reviewed at engine tear down. It has been determined
that these components do not need to be replaced:

Acceptable Cylinder that Does Not Appear
Uniform (Zebra Stripes)

3409678

•
3339531

While performing this repair on 2010 and 2011 vehicles
built before March of 2011, it should be verified that the
high pressure fuel pump (P/N 12641847), balance
chain (P/N 12645237), balance chain tensioner
(P/N 12649233), and timing chain kit (P/N 12635447)
have been installed in this engine in a previous repair.
Refer to IVH and check the parts listed in the prior
repairs. If these parts have not been installed, they
should be replaced at the time that the piston and rings
are replaced. If they have been replaced, do not
replace them again. Engines in 2012 and 2013 vehicles
do not need the balance chain or fuel pump inspected.
Also when performing this repair, several other parts
should be inspected for excessive wear and/or damage
and replaced if necessary:
– Balance chain guides
– Timing chain guides
Important: DO NOT use any abrasive wheels/
materials to clean any mating surfaces. Only Plastic
scrapers should be used. Please refer to the latest
version of Corporate Bulletin Number 00-06-01-012.

Camshafts and roller follower will have wear
markings. This is normal and do not need to be
replaced (refer to picture above).

3409680

•

•

Valves stems may have deposits build up on
them. These deposits are characteristic of a direct
inject engine. The valves stems do not need to be
cleaned as they are not affecting engine
performance (Refer to picture above).
The oil pump does not need to be replaced as the
low oil level operation did not damage the pump.

Bulletin No.: 13-06-01-003C
•

September, 2013

The camshaft actuators do not need to be
replaced at this time. The vehicle may have
arrived with the engine knocking. If the oil level
was 1 1/2 - 2 quarts low, it was the lack of oil
causing the actuator noise.
• Rod bearings can be reused if there is not any
excessive scoring. Some light wear marks are
acceptable.
Important: Rod bearings must be marked to identify
the proper location to ensure bearings are returned to
their original positions.
The final step is to verify that ECM OLM calibration has
been installed before the vehicle is returned to the
customer.
Important: DO NOT use any abrasive wheels/
materials to clean any mating surfaces. Only Plastic
scrapers should be used. Please refer to the latest
version of Corporate Bulletin Number 00-06-01-012.

Parts Information

Page 3

Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation

Description

Labor
Time

4080008*

Oil Consumption Test Setup

0.2 hr

Add

Piston, Connecting Rod and
Bearing Replacement

9.3 hrs

Add

To Replace Fuel Pump
(2010-2011 Models Built Prior to
March 2011 Only)

0.7 hr

Add

To Replace Balance Shaft Chain
and Tensioner (2010-2011
Models Built Prior to March
2011 Only)

0.8 hr

Add

To Replace Timing Chain
(2010-2011 Models Built Prior to
March 2011 Only)

0.5 hr

*This is a unique labor operation for bulletin use only. It will
not be published in the Labor Time Guide.

Part Number

Description

12646457

PISTON KIT, ENG

12659419

RING KIT, PSTN

12637166

GASKET KIT, CYL HD

12609291

SEAL, CM/SHF

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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