NUT 9H6932 - Caterpillar

An engine which operates outside of normal conditions is operating in a severe service application.An engine that operates in a severe service application may need more frequent maintenance intervals in order to maximize the following conditions:
Reliability
Service lifeThe number of individual applications cause the impossibility of identifying all of the factors which may contribute to severe service operation. Consult your Caterpillar dealer for the unique maintenance that may be necessary for your engine.An application is a severe service application if any of the following conditions apply:Severe Environmental Factors
Frequent operation in dirty air
Frequent operation at an altitude which is above 1525 m (5000 ft)
Frequent operation in ambient temperatures which are above 32° C (90° F)
Frequent operation in ambient temperatures which are below 0° C (32° F)Severe Operating Conditions
Frequent operation with inlet air which has a corrosive content
Operation with inlet air which has a combustible content
Operation which is outside of the intended application
Operation with a plugged fuel filter
Extended operation at low idle (more than 20% of hours)
Frequent cold starts at temperatures below 0° C (32° F)
Frequent dry starts (starting after more than 72 hours of shutdown)
Frequent hot shutdowns (shutting down the engine without the minimum of 2 minutes to 5 minutes of cool down time)
Operation above the engine rated speed
Operation below the peak torque speed
Operating with fuel which does not meet the standards for distillate diesel fuel as stated in Special Publication, SEBU6250, "Caterpillar Machine Fluids Recommendations", "Distillate Diesel Fuel"
Operating with a blend of distillate fuel which contains more than 20 percent biodieselImproper Maintenance Procedures (Maintenance Procedures Which May Contribute to a Severe Service Application)
Inadequate maintenance of fuel storage tanks from causes such as excessive water, sediment, and microorganism growth.
Extending maintenance intervals beyond the recommended intervals
Using fluids which are not recommended in Special Publication, SEBU6250, "Caterpillar Machine Fluids Recommendations"
Extending maintenance intervals for changing the engine oil and engine coolant without S O S validation
Extending maintenance intervals for changing air filters, oil filters, and fuel filters
Failure to use a water separator
Using filters which are not recommended by Special Publication, PEWJ0074, "2008 Cat Filter and Fluid Application Guide"
Storing the engine for more than 3 months but less than 1 yr (For information about engine storage, refer to Special Publication, SEHS9031, "Storage Procedure for Caterpillar Products")