CK-4 Engine Oil: What You
Need To Know
CK-4 engine oils have been available since late 2016, but if you’re like many heavy equipment owners, you still have questions about them. Get answers here.
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 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 Happens if I don’t Use it in My Tier 4 Products?
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
WHAT IF I’M NOT RUNNING TIER 4 MACHINES?
If your fleet is powered by Tier 3 or older engines, you don’t need newer oil. Just be aware that switching to Tier 4 engines and higher-grade oil not only improves emissions performance, but also boosts productivity and fuel economy.
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. Read about Cat® diesel engine oil here or contact your Cat dealer for details.
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