Engine - Oil Usage Testing and Reporting
2007 Service BulletinsTSB SB07-01-S001
ISSUE DATE: JANUARY 2007
Engine Oil Usage Testing and Reporting (This Bulletin Supersedes SB04-01-S004)
Affected Vehicles
All Light Duty Isuzu Vehicles
Service Information
This bulletin has been revised to include new mileage information for Ascender, i-280, i-290, i-350, and i-370 vehicles and to update Model Years.
Before performing any warranty repairs, based on a customer's complaint of excessive engine oil consumption, the attached Engine Oil Usage Test/Report must be completed in full.
The updated Engine Oil Usage Test / Report is divided into two parts, PROCEDURE # 1 and PROCEDURE # 2.
Procedure # 1, the inspection and testing portion of the Engine Oil Usage Test / Report, are eligible for warranty submission. Procedure # 1 warranty claim may only be submitted ONE time per vehicle. Review Procedure # 1 Results and perform the appropriate action.
Complete all steps in Procedure #1 before continuing on to Procedure # 2 (if required).
Procedure # 2, the validation portion, is NOT reimbursable under warranty. Complete all steps in Procedure # 2. Review Procedure # 2
Results and perform the appropriate action.
The Technician, Service Manager and Customer are to acknowledge the findings by signing and dating the bottom of the Engine Oil
Usage Test / Report. Attach a copy of the completed report to the back of the Repair Order (R/O) hard copy and provide a copy to the customer.
NOTE:
1. Normal authorization procedures must be followed for such repairs.
2. Information released on paper and electronic format prior to bulletin release cannot be updated.
For the most current and up to date information refer to website.
All engines require oil to lubricate and protect the load bearing and internal moving parts from wear including cylinder walls, pistons and piston rings. When a piston moves down its cylinder, a thin film of oil is left on the cylinder wall. During the power stroke, part of this oil layer is consumed in the combustion process. As a result, varying rates of oil consumption are accepted as normal in all engines.
Oil Consumption
The accepted rate of oil consumption for engines used in Ascender, i-280, i-290, i-350, and i-370 vehicles is 1 quart (0.946 liter) in 2,000 miles (3200 km).
The accepted rate of oil consumption for engines used in Trooper (UX), Axiom (UP), VehiCROSS (VX), Rodeo (UE), and Rodeo Sport/Amigo (UA) vehicles is 1 quart (0.473 liter) in 1,000 mi (1600 km).
IMPORTANT:
Always refer to the Isuzu Service Policies and Procedures Manual for specific details on warranty coverage and policies.
This rate only applies to personal use vehicles, under warranty, that are driven in a non-aggressive manner and maintained in accordance with the appropriate maintenance schedule, with less than 36,000 miles (58,000 km), driven at legal speeds in an unloaded (for trucks) condition.
IMPORTANT:
This rate does not apply to vehicles that are driven in an aggressive manner, at high RPM, high speeds, or in a loaded condition (for trucks). Oil consumption for vehicles driven under these conditions will be more.
Many factors can affect a customer's concern with oil consumption. Driving habits and vehicle maintenance vary from owner to owner. Thoroughly evaluate each case before deciding whether the vehicle in question has abnormal engine oil consumption.
Gasket and External Leaks
Inspect the oil pan and engine covers for leakage due to overtightened, damaged, or out of place gaskets. Inspect oil lines and fittings for signs of leakage.
Improper Reading of the Oil Level Indicator (Dipstick)
Verify that the dipstick tube is fully seated in the block. When checking the oil level, make sure the dipstick is wiped clean before taking an oil level reading and fully depress the dipstick until the shoulder bottoms out on the dipstick tube. The dipstick should be the proper part number for the engine/vehicle that is being checked.
IMPORTANT:
Refer to the Owner Manual for checking and adding engine oil.
Not Waiting Long Enough After Running Engine to Check Oil Level
Some engines require more time than others for the oil to drain back into the crankcase. To assure a sufficient amount of oil has drained back to the crankcase, and an accurate reading can be obtained, the vehicle should be allowed to sit for at least 15 minutes, after the engine has been shut off, before taking an oil level reading. In order to ensure accurate results, the temperature of the oil should be close to the same temperature as the last time the oil level was checked.
Improper Oil Fill After an Oil Change
Following an oil change, verify that the proper amount and type of oil was put in the engine and that the oil level on the dipstick is not above the full mark or below the add marks. Refer to the Owner's Manual or Service Manual for information on recommended oil quantity, viscosity, and quality.
Aggressive Driving, High Speed or High RPM Driving
Aggressive driving and/or continuous driving at high speeds/high RPM will increase oil consumption. Because this may not always be an everyday occurrence, it is hard to determine exactly how much the oil economy will be affected.
Towing or Heavy Usage
Towing a trailer will increase oil consumption and may cause oil consumption to fall below the normal accepted rate referenced in this bulletin for an unloaded vehicle in a personal use application. Large frontal area trailers will further increase the work required from the engine, especially at highway speeds, and thus increases the rate of oil consumption.
Crankcase Ventilation System
Verify that the positive crankcase ventilation (PCV) system is operating properly. Blockages, restrictions, or damage to the PCV system can result in increased oil use.
Oil Dilution (Fuel and Water)
On vehicles that are usually driven short distances, less than 5 miles (8 km), especially in colder weather, unburned fuel and condensation generated from cold engine operation may not get hot enough to evaporate out of the oil. When this occurs, the dipstick may indicate that the oil level is over-full. Subsequent driving on a trip of sufficient length to enable normal engine operating temperature for 30 minutes or more, in order to vaporize excess moisture and fuel, may give the customer the impression of excessive oil consumption.
Engine Temperature
If an engine is run at overheated temperatures (see Owner's Manual or Service Manual) for more than brief periods, oil will oxidize at a faster than normal rate. In addition, gaskets may distort, piston rings may stick, and excessive wear may result. Verify that all cooling system components are in proper working order.
Engine Wear
Piston scuffing, excessive piston-to-wall clearance, tapered or out of round cylinders, worn, damaged or improperly installed valve guides, seals and piston rings will all cause an increase in oil consumption.
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