#11-06-01-007: Engine Oil Consumption with Active Fuel Management (AFM) (Install Oil Pan Gasket and Clean Carbon from Cylinder) - (Nov 22, 2011)
Subject: Engine Oil Consumption with Active Fuel Management (AFM) (Install Oil Pan Gasket and Clean Carbon from Cylinder)

Models: 2008-2009 Buick LaCrosse/Allure
2006-2007 Chevrolet Monte Carlo
2006-2009 Chevrolet Impala SS
2005-2008 Pontiac Grand Prix GXP
Equipped with V8 Engine RPO LS4

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). Verify that the induction system is assembled correctly and that there is no evidence that the engine has been ingesting dirty air due to a mis-assembled induction system. Also verify that the PCV system is functioning properly. If diagnostic procedures indicate that oil consumption is piston/piston ring related, verify that oil consumption is greater than 0.946 L (1 qt) in 3,200 km (2000 mi). If these conditions are met and oil consumption is greater than 0.946 L (1 qt) in 3,200 km (2000 mi), perform the service indicated in this bulletin.
Cause

This condition may be caused by 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.

To correct this condition, perform the piston cleaning procedure as described in this document, and install the 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 the piston assemblies (piston and rings) with new parts.
Correction
A new oil pan gasket has been released. Technicians should replace the oil pan gasket with GM P/N 12643081. This oil pan gasket has the AFM shield incorporated into the gasket. Refer to SI for Oil Pan Gasket Replacement.

To correct this condition, perform the piston cleaning procedure as described in this document, and install the 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. Verify the oil consumption concern following Corporate Bulletin Number 01-06-01-011G. If oil consumption is found, continue on with this bulletin.
2. Remove the spark plugs and ensure that none of the pistons are at top dead center (TDC).
3. Clean the pistons by putting 118-147 ml (4-5 oz) of Upper Engine and Fuel Injector Cleaner, GM P/N 88861802 (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 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.
4. Remove the oil pan. Refer to Oil Pan Replacement in SI.
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.
5. Reinstall the spark plugs. Replace the spark plugs if necessary due to full of carbon. Refer to the parts catalog.
6. Reinstall the oil pan. Refer to the Oil Pan Installation procedure in SI. Replace the oil pan gasket.
7. 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.

Parts Information

Part Number: 12643081 Oil Pan Gasket
Part Number: 88861802 (in Canada, use 88861804) CLEANER, F/INJR 16 OZ LIQUID POUR (Upper Engine and Fuel Injector Cleaner)

 

About dang time! Great information. Thanks!

 

I just got a new pan gasket a few months ago. i hope it was this one.

 

So they 5.3 V8s use oil?? ouch not sure I'd want one anymore lol jkjk but seriously if its a common problem I havent heard much about it glad to know.

 

it is common after 30k-40k. I havent had the issue and i am almost at 40k. Some ppl just turn DoD or AFM off.

 

I really havent had any problems with this. hmm

 

thats good! you may never have any trouble. i havent had any trouble either. just thought i would keep those with an LS4 informed.

 

Kind of an update. I called my local dealership today. Talked with a guy i know in service. he said that if you arent experiencing the oil consumption issue there is nothing preventative they can do. The oil pan gasket looks to be the same part number it was before.

sounds like to me that if it is burning oil they put new rings on the pistons and install the new oil pan gasket. They have done 3-4 LS4s so far.

looks like I will still be turning off DoD/AFM in the spring.

 

Zach--just gonna let you know that the part numbers you gave above match the part numbers on the receipt that i got the other day. Even the cleaner part #'s match. Good work

 

Did u get your car back? If do how is it?