Caterpillar Machine Fluids Recommendations
Contamination Control
Defining Contamination
Contaminants are any substance in the system that is not intended to be in the system. Contamination is the wear particles, water, fibers, dirt, dust, or products of combustion that are suspended in the oil or the fuel. The size of these particles is much smaller than the size of a human hair. A human hair is 80 microns in diameter. The newer machine systems operate at higher pressure. The newer machine systems are designed with closer tolerances. This emphasizes the importance of filter maintenance, as well as clean fuels and clean lubricants.
Measuring Cleanliness
The fluid cleanliness can be measured by taking fluid samples from the machine hydraulic compartments and from drive train compartments and having them analyzed by your Caterpillar dealer. The analysis is similar to monitoring the engine oil with S·O·S Services Oil Analysis. The amount of particulate matter is expressed in ISO (International Organization for Standardization) units. This standard of cleanliness is expressed as two numbers. An example of a standard for cleanliness is ISO16/13. The first number (16) relates to the number of particles that are larger than 6 microns in size. The second number (13) relates to the number of particles that are larger than 14 microns in size. There are 28 code numbers on the ISO Code scale. Each code has a given range of particles per milliliter. The smaller code number designates fewer particles.
Note: Currently, sample pretreatment is the recommended way to accurately complete the particle count measurement process. Contact your local Caterpillar dealer S·O·S Services Lab for guidance.
Standards for Machine Systems
Maintain the machine systems as close as possible to the standards for the new machines.
Recommended Maximum Contamination Levels - Through fluid system testing and accepted industry wide contamination targets, a maximum contamination level has been established for various machine systems (see table 1 below). If a system is maintained at or below this target, the system should not see any harmful effects from contamination throughout its engineered life.
Table 1 Caterpillar Recommended Cleanliness Targets
Hydraulic Systems (Implement & Steering) ISO 18/15
Vehicles With Electronic Controled Transmissions ISO 18/15
Vehicles With Mechanical Transmissions ISO 21/17
Fill oils ISO 16/13
Non-Pressurized, Non-Filtered Compartments. Target To Be Established
Although older technology machines may not be able to consistently maintain the recommended cleanliness targets of today's advanced models, the same contamination control intervention measures and subsequent service procedures should be used on all Caterpillar products.
Note: Do not use the particle count for the evaluation of the engine's oil. Large amounts of soot are produced within an engine. Evaluate the engine's oil by using S·O·S Services Oil Analysis.
Recommendations or Practices
Some guidelines to use for controlling contaminants are listed in this Special Publication. By maintaining a low contaminant level, a machine's maintenance cost can be controlled. The machine's productive life may also be increased.
Follow the general guidelines for controlling contaminants.
1. Use fuels that meet Caterpillar diesel fuel specifications. Filter all diesel fuel through a 4 or less micron(c) absolute filter when you refuel the machine. Make sure that you use Caterpillar Advanced Efficiency Fuel Filters for all engines that have a high pressure fuel injection system.
NOTICE
In order to meet expected fuel system component life, 4 micron(c) absolute or less secondary fuel filtration is required for all Caterpillar diesel engines that are equipped with common-rail fuel systems, and for all Caterpillar diesel engines that are equipped with unit injected fuel systems. For all other Caterpillar diesel engines (mostly older engines with pump, line and nozzle type fuel systems), the use of 4 micron(c) absolute or less secondary fuel filtration is strongly recommended. Note that all current Caterpillar diesel engines are factory equipped with Caterpillar Advanced Efficiency 4 micron(c) absolute fuel filters.
In order to obtain additional information on Caterpillar designed and produced filtration products, refer to the "Reference Material" article, "Filters" and "Miscellaneous" topics in this Special Publication, and then contact your Caterpillar dealer for assistance with filtration recommendations for your Caterpillar machine.
2. Use only coolants that are recommended by Caterpillar for your machine. Follow the recommended maintenance procedure for the cooling system in the Operation and Maintenance Manual for your machine.
3. When you add oil to a machine, filter the oil through a 5 or less micron(c) absolute filter to ensure that it is clean.
4. Refer to the machine's Operation and Maintenance Manual for the required maintenance for all machine compartments.
5. Perform scheduled S·O·S Services Oil Analysis for contamination in order to maintain the recommended ISO cleanliness level. Refer to the S·O·S Oil Analysis section in this Special Publication. The particle count analysis can be performed by your Caterpillar dealer. Particle count can be conducted during the scheduled S·O·S Services Oil Analysis for the compartment. Extra oil samples are not required for the particle count sampling.
6. Maintain the engine's intake air filters. This will minimize contamination at the engine's air intake system.
