Your CK-4 Engine Oil Questions Answered





CK-4 engine oils have been available since late 2016, but if you’re just acquiring your first machine with a Tier 4 engine, they might be new to you. Here are answers to some of the most common questions about these oils.


What is CK-4 Oil?

It’s the newest generation of diesel engine oil. Although it was developed especially for Tier 4 engines, you can use it in older models, too. The industry calls that “backwards-compatible."


Wasn’t CJ-4 Oil the Go-To Lubricant For Tier 4 Engines?

CJ-4 oil has been the standard for high-efficiency, low-emissions engines since its introduction more than a decade ago — but that was about the time the first iPhone came out. Think about how rapidly technology has changed since then. The newest engines on the market are loaded with features that boost performance, improve fuel economy and reduce emissions. They’ll benefit from an upgraded oil.


What's different about CK-4 oil?

It provides the highest level of protection and performance for engines equipped with emission-control technologies. Specifically, it:

  • Resists oxidation, even under high-heat conditions, minimizing engine deposits and extending service intervals
  • Reduces aeration, which helps prevent oil breakdown, cavitation and corrosion
  • Improves shear stability, which translates into consistent viscosity under high loads for better lubrication and protection

Bottom line — CK-4 oil is the new standard for off-highway equipment.


What's different about CK-4 oil?

Using CK-4 oil is the best way to optimize the performance, fuel economy and durability of Tier 4 engines. That said, CJ-4 oil will not damage a Tier 4 product, but beware of older oils including CH-4 and CI-4. They may:

  • Plug the diesel particulate filter, causing excessive regeneration and reducing engine life
  • Deactivate or “poison” the catalytic material in the aftertreatment system, rendering it ineffective
  • Reduce operating efficiency, jeopardizing performance, life and operating costs


If I’m replacing CJ-4 oil with CK-4, do I buy the same viscosity grade I’m using now?

Yes. In off-highway equipment, it’s a simple change. Just buy the grade you’re currently using.


Are all brands of CK-4 oil the same?

No. The CK-4 standard, established by the American Petroleum Institute (API), represents a minimum requirement. Some oils, including those offered by Caterpillar, exceed the standard.


Are Cat® oils really different?

It’s hard to see what sets Cat® fluids apart from the competition — but when you take a closer look at the results, the difference is clear. Your system runs cleaner. Your machine performs better. Your components last longer. See for yourself how the system design of Cat fluids delivers real results, then check out the full lineup of Cat Oils.



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