Seville STS V8-4.6L VIN 9 (1998)
Positive Crankcase Ventilation Valve: Customer Interest
Engine - Higher Than Normal Oil Consumption
Bulletin No.: 02-06-01-009C
Date: October 23, 2003
TECHNICAL
Subject:
Higher than Expected Oil Consumption (Clean Piston Rings)
Models:
1996-2000 Cadillac Concours
1996-2002 Cadillac Eldorado
1996-2003 Cadillac DeVille, Seville
with 4.6L Engine (VINs Y, 9 - RPOs LD8, L37)
Supercede:
This bulletin is being revised to add parts information. Please discard Corporate Bulletin Number 02-06-01-009B (Section 06 - Engine).
VIN Breakpoints
Condition
Some customers may comment on higher than expected oil consumption. The typical customer with this condition comments on consumption in the
range of 0.946L (1 qt) of oil used in 1600-2250 km (1000-1400 mi) of operation. The oil consumption rate and possible oil consumption areas, as per
Corporate Bulletin # 01-06-01-011 dated March, 2001, should be verified prior to performing the ring cleaning procedure below. The standard for
acceptable oil economy and the method for determining oil economy are outlined in Corporate Bulletin # 01-06-01-011.
The following text is referenced from Corporate Bulletin # 01-06-01-011 for your convenience. Oil Consumption:
The accepted rate of oil consumption for engines used in the vehicles referenced is 0.946L (1 qt) in 3200 km (2000 mi). This rate only applies to
personal use vehicles, under warranty, maintained in accordance with the appropriate maintenance schedule, with less than 58,000 km (36,000 mi), or
80,450 km (50,000 mi) for Cadillac, driven at legal speeds in an unloaded (for trucks) condition.
Cause
Although there are several reasons for less than expected oil economy described in Corporate Bulletin # 01-06-01-011, one area not covered is reduced
sealing ability of the rings. Through normal usage, combustion chamber deposits may build up to the point that the movement of the rings could become
restricted and prevent the rings from wiping all of the oil off the cylinder walls and allowing it to be burned in the combustion process.
Correction
A new ring cleaning process has been developed to restore the function of the rings. Once the possible oil consumption areas in Corporate Bulletin #
01-06-01-011 have been eliminated, this cleaning process should be performed. If the oil economy has not improved to 0.946L (1 qt) in 3200 km (2000
mi) after cleaning, it may be necessary to replace the piston rings. Be sure to install the second compression ring notch side down. If the vehicle is a 2000
to 2003 with an oil consumption concern with less than 25,000 miles on the vehicle, then skip the cleaning process and install the new rings.
Important:
