Engine - Oil Consumption Test Procedure
Group: ENGINE MECHANICALNumber: 03-20-001
Date: FEBRUARY, 2003
Model: ALL
Subject
OIL CONSUMPTION TEST PROCEDURE
DESCRIPTION:
The following information and procedure is provided to assist you in documenting and verifying excessive oil consumption.
An engine that is operating properly will use some amount of oil. A thin oil film is responsible for lubricating the cylinder walls and preventing premature ring and cylinder wear. This oil film is consumed during the combustion process and the amount consumed can add up over many hours of engine operation.
Engine oil usage will vary based on many factors including ambient temperature, engine size, quality and viscosity of oil, and driving habits.
The first 1,200 miles are very important for the engine to break in and engine oil usage may be slightly greater during this time period. The oil consumption test (outlined below) should not be performed on a vehicle with less than 1,200 miles.
TEST PROCEDURE:
1. Check the oil level on the dipstick and record the reading. Change oil and filter under the normal maintenance procedure. Note the condition of the oil. Does it look like the oil has been changed at the proper intervals?
2. Arrange with the customer to visit the dealership every time the engine needs oil for the duration of the test. At every visit, the oil consumption sheet must be filled out including mileage, date, amount of oil added and the technician's initials. For a proper diagnosis, the amount of oil consumed over a known mileage should be checked three times and then averaged.
The accumulated mileage divided by the total amount of oil added will give the consumption rate in miles per quart (see example below). If the oil consumption rate is greater than 1000 miles per quart, further diagnosis may be required.