Diesel fuel serves three major purposes in fuel systems: providing the energy source for the combustion process, removing heat from fuel high pressure injection components and providing lubrication for the high friction moving parts in the fuel system. When fuel is of low quality you can have severe reliability issues so the need for regular fuel testing is of great importance.

Download the CAT SOS fluid testing guide here

Fuel is likely to be the largest single expense faced by diesel engine operators on a day to day basis. It is important  to ensure that the fuel you have in your tanks is of highest quality.

In addition to reducing engine performance, contaminated fuel can cause abnormal or catastrophic wear in fuel pumps and injectors.

Testing of your fuel determines if inherent qualities fall within required limits thus ensuring that your diesel fuel remains in good health.

Cat SOS fuel testing factors.

• Biodiesel Content
• Oxidation Stability
• Particle Count
• Pour Point
• Sulfur Content
• Viscosity
• Water Content
• Cetane Index
• Cloud Point
• Microbial Growth
• Distillation Curve
• Elemental Analysis
• Cold Filter Plugging Point
• Density
• Flash Point

How does the testing work?

You simply purchase the SOS fuel test kit from a Caterpillar dealer or agent, depending on your location around the world you may have the options of several tests to choose from with varying costs, order just the basics at a cheaper price to “the works testing” at more expense.

You extract your sample to the test bottle, apply and mark the labels with your data. Get the sample back to the dealer for the test process which will take a day or two for completion.

You can then get the results back via an email, SMS, fax or log-in to the SOS online portal to view the data of your test.


Cat offers fast, inexpensive and accurate fuel testing, they also have test kits for coolant and oil.

One of the best ways to test your engines fluids to ensure they are in good condition.

How to use the Cat SOS diesel fuel test kit