Best Practices

Best Practices for OAT Coolant

Never Mix OAT with Regular Coolant

  • Mixing coolants can cause a loss of stability in the corrosion inhibitor, cavitation erosion, and gelling damage. This type of damage is not covered by your warranty, and repairs can cost thousands of dollars.
  • Adding as little as 10% of regular coolant in an OAT system is enough to cause damage to your machine.
  • Look for the OAT decal before adding or changing coolant to ensure you don't mix coolants and cause gelling inadvertently.

Selecting Coolants

  • Do not risk using OAT coolants from other manufacturers, unless they specifically meet CASE's MAT3624 material requirements.
  • Use the ATSM number, not the coolant color, for reference when selecting your coolant.

Mixing OAT with Water

  • Mix half OAT and half water ratio, which will protect cooling systems to -35° F (-37° C).
  • Only use de-ionized water with OAT coolant. Tap, hard, softened or sea water will reduce the coolant life and can cause deposits to form, creating hot spots and cavitational corrosion.

Avoid Machine Damage

  • Do not use anti corrosive additives in an OAT cooling system. Although these additives are commonly used in ethylene glycol fluids, they can cause premature wear in your machine.
  • Only use machines with chemical resistant hosing. OAT coolant will react with PVC, rubber and Viton seals, creating leaks over time.

Note: Use of OAT is not recommended for older machines.
If you choose to run OAT in an older application, the cooling system must be flushed. The nitrate level must not be higher than 20 ppm.

Deter Theft Through Equipment Security
  • All new Case Tier 4b vehicles with Fiat Power Train (FPT) engines that are in the ≥ 56 kW emissions category require OAT coolant.
  • Decals indicating that OAT coolant must be used are affixed to the tank or radiator.
Oil Requirements

Engine oil requirements may have changed, too, due to Tier IV emissions technologies.

  • Low-ash CJ-4 oil is required for machines with DPF
  • Non-DPF machines can run either CI-4 or low-ash CJ-4 oil

There is no industry standard for CJ-4 oil additives. Don't risk premature engine wear by using oil that is not formulated for your machine.