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Under severe or dusty conditions, or where average operating speeds are less than 40 km/h (25 mph), such as inner city garbage compactors, delivery trucks or drill rigs, the maintenance interval should be reduced to 250 Service Hours or 5000 km (3000 Miles), whichever occurs first.
Perform all previous maintenance as outlined in the Maintenance Intervals along with the maintenance requirements of this interval.Scheduled Oil Sampling (S O S)
Obtain Sample
To compliment a good preventive maintenance program, Caterpillar recommends using S O S at regular scheduled intervals to monitor the condition and maintenance requirements of your engine. Each oil sample should be taken when the oil is warm and well mixed to ensure that the sample is representative of the oil in the compartment.There are several methods used to obtain S O S samples.*Use a sampling gun inserted into the sump.*Use a valve installed for samples.*Use the drain stream when changing oil.Caterpillar recommends using the first or second method. If these methods are not feasible, then use the drain stream. When using the drain stream to obtain the oil sample, do not sample from the first or final draining. The oil at the beginning or end of the drain stream is not mixed well enough to be representative of the oil in the crankcase.Oil condition is evaluated with infrared analysis. This test determines the presence and measures the amount of soot, sulfur products, oxidation, and nitration products in the oil. Infrared analysis can also assist in customizing (reducing, maintaining or extending) oil change intervals for particular conditions and applications.Infrared analysis should always be accompanied by wear element analysis and chemical and physical tests to assure accurate diagnosis. Consult your GMC TopKick/Chevrolet Kodiak dealer, who is an authorized Cat 3116 engine dealer, for complete information and assistance in establishing an S O S program for your engine.Engine Oil and Filter
Replace Oil and Filter
The percentage of sulfur in the fuel will affect the engine oil recommendations. Fuel sulfur is chemically changed during combustion to form sulfurous and sulfuric acid. These acids chemically attack metal surfaces and cause corrosive wear.Certain additives used in lubricating oils contain alkaline compounds that are formulated to neutralize these acids. The measure of this reserve alkalinity in a lubricating oil is known as its Total Base Number (TBN). Higher engine oil TBN values are essential to neutralize the acids from combustion gases and to minimize corrosive wear.If the fuel has over 0.5% sulfur content, the engine oil must have a TBN of 20 times the percentage of fuel sulfur as measured by the ASTM (American Society of Testing Materials) D-2896 method.If the sulfur content in the fuel is greater than 1.5% by weight, use an oil with a TBN of 30 and also reduce the oil change interval by one half.Refer to the Fuel Specifications and Lubricant Specifications sections of this publication for more information.Drain the crankcase with the oil warm and the engine stopped to allow for the draining of waste particles that are suspended in the oil. As the oil cools, suspended waste particles will settle on the bottom of the crankcase and will not be removed with the draining oil.Failure to follow this recommended procedure would result in these waste particles being recirculated through your engine lubrication system with the new oil. 1. Remove the crankcase drain plug and allow the oil to drain.2. Install the crankcase drain plug and tighten it to 70 14 N m (50 10 lb ft), or close the crankcase drain valve. 3. Use a 2P8250 Filter Wrench to remove the oil filter.4. Wipe the sealing surface of the filter element mounting base. Make sure all of the old gasket is removed. Make sure to use the correct Caterpillar oil filter element for your engine arrangement.Your Caterpillar oil filter element was built to Caterpillar specifications to ensure you receive a quality part at a competitive price. Caterpillar oil filter elements are inspected as part of an inspection program that was developed to ensure compliance with established quality standards.Caterpillar is constantly testing oil filter elements for the purpose of modifying and/or incorporating the latest technological advancements into current filter designs.Failure to use a Caterpillar oil filter element as recommended could result in the use of an inferior product. Some non-Caterpillar oil filters do not have a sufficient micron rating. This allows larger debris particles to pass unfiltered into the engine. Some non-Caterpillar oil filters consist of inferior material that can split at the seams and allow unfiltered oil into the engine. The bonding between the filter material and filter end cap on some non-Caterpillar oil filters is inadequate and therefore, upon failure, will allow unfiltered oil into the engine.Use of an oil filter element not recommended by Caterpillar could result in severe engine damage to your engine bearings, crankshaft, etc., as a result of the larger debris particles or unfiltered oil entering your engine.
Do not fill the oil filters with oil before installing them. This oil would not be filtered and could be contaminated. Contaminated oil will cause accelerated wear to the engine.
5. Apply a small amount of clean engine oil to the new filter element gasket.6. Install the new filter element by hand until the gasket contacts the base. Tighten the filter 3/4 of a turn more. Do not overtighten. 7. Remove the oil fill cap (1) and fill the crankcase.
If equipped with an auxiliary oil filter, extra oil must be added when filling the crankcase. Refer to the GMC TopKick/Chevrolet Kodiak Owner's Manual for the proper refill quantity. If the extra oil is not added, the engine may starve for oil. Do Not overfill the crankcase.
8. Before starting the engine, ensure your oil level is between the ADD and FULL marks