Diesel Engine Oil CH-4
Two SAE viscosity grades supported by supplied product inspection data.
A heavy-duty diesel engine oil range available in SAE 15W-40 and 20W-50. The page presents the measured viscosity, cold-cranking, HTHS, flash point, pour point, cleanliness and foaming results from the supplied inspection reports, together with the official API CH-4 service-category context and responsible 30,000 km drain-interval guidance.
A measured-data story for dependable diesel lubrication
The following benefits are explained using the actual physical-property results in the supplied inspection reports—not invented performance percentages.
High-Temperature Oil-Film Strength
Measured HTHS viscosity is 4.19 mPa·s for 15W-40 and 4.21 mPa·s for 20W-50, both above the report minimum of 3.7 mPa·s.
See HTHS data →Controlled Low-Temperature Cranking
CCS results are 5,823 mPa·s at -20°C for 15W-40 and 8,126 mPa·s at -15°C for 20W-50, within their respective quality limits.
Compare grades →Volatility & Temperature Margin
Open-cup flash points are measured at 226°C and 235°C. The reported pour points are -33°C for 15W-40 and -34°C for 20W-50.
View temperature data →Cleanliness & Foam Control
Both reports record no water and no mechanical impurities. Reported foaming results are 0/0 for every listed test sequence.
Review quality checks →For high-speed four-stroke diesel engines where CH-4 is specified
Use CH-4 only where the engine or equipment manufacturer permits this API category, viscosity grade and intended service interval.
Heavy work. Clear grade selection.
Typical target equipment can include commercial vehicles, construction machinery, agricultural equipment and stationary diesel engines—subject to OEM approval.
Commercial Diesel Fleets
Trucks and buses with high-speed four-stroke diesel engines whose manuals permit API CH-4 and the selected viscosity grade.
Construction Equipment
Suitable excavators, loaders, generators and site machinery operating under heavy loads.
Agricultural Machinery
Selected tractors, harvesters, pumps and farm engines where API CH-4 is specified by the manufacturer.
Stationary Diesel Engines
Industrial or standby equipment requiring the stated service category and viscosity.
Complete comparison of the supplied 15W-40 and 20W-50 reports
Values below are transcribed from the supplied Shengxiang product inspection reports. They represent the stated measured results and quality indices for those reports.
| Analysis item | 15W-40 index | 15W-40 result | 20W-50 index | 20W-50 result | Test method |
|---|---|---|---|---|---|
| Appearance | Transparent | Transparent | Transparent | Transparent | Visual inspection |
| Kinematic viscosity @ 100°C | 12.5–16.3 mm²/s | 14.80 mm²/s | 16.3–21.9 mm²/s | 19.90 mm²/s | GB/T 265 |
| Kinematic viscosity @ 40°C | Reported value | 112 mm²/s | Reported value | 174 mm²/s | GB/T 265 |
| Viscosity index | Reported value | 136 | Reported value | 132 | GB/T 2541 |
| Pour point | ≤ -25°C | -33°C | ≤ -20°C | -34°C | GB/T 3535 |
| Water content, volume fraction | None | None | None | None | GB/T 260 |
| Mechanical impurities, mass fraction | None | None | None | None | GB/T 511 |
| Flash point, open cup | ≥ 205°C | 226°C | ≥ 215°C | 235°C | GB/T 3536 |
| CCS low-temperature cranking | ≤ 7,000 mPa·s @ -20°C | 5,823 mPa·s | ≤ 9,500 mPa·s @ -15°C | 8,126 mPa·s | GB/T 6538 |
| HTHS viscosity @ 150°C, 10⁶ s⁻¹ | ≥ 3.7 mPa·s | 4.19 mPa·s | ≥ 3.7 mPa·s | 4.21 mPa·s | NB/SH/T 0703-2020 |
| Foaming tendency / stability | 24°C ≤10/0; 93.5°C ≤20/0; after 24°C ≤10/0 mL/mL | 0/0; 0/0; 0/0 | 24°C ≤10/0; 93.5°C ≤20/0 mL/mL | 0/0; 0/0 | GB/T 12579 |
| Determination | PASS | PASS | Inspection report | ||
Units and conditions are shown as stated or standardized from the supplied reports. Blank quality-index fields in the original reports are presented here as “Reported value.”
What each laboratory property tells the buyer
Kinematic Viscosity
Shows how readily the oil flows at 40°C and 100°C. The measured 20W-50 values are higher than the 15W-40 values, confirming the heavier operating-viscosity profile.
Viscosity Index
Indicates the rate of viscosity change with temperature. The reported VI is 136 for 15W-40 and 132 for 20W-50.
Pour Point
A laboratory indication of low-temperature flow. The supplied reports show -33°C for 15W-40 and -34°C for 20W-50; neither value is a direct engine-start temperature recommendation.
Open-Cup Flash Point
The lowest reported test temperature at which vapour can ignite momentarily under the specified method. Results are 226°C and 235°C.
Cold Cranking Simulator
Represents apparent viscosity during low-temperature cranking. The grades are tested at different specified temperatures, so the two CCS numbers should not be compared as if measured under identical conditions.
High-Temperature High-Shear
Reflects viscosity under severe high-temperature and high-shear test conditions. Both results exceed the stated minimum of 3.7 mPa·s.
15W-40 or 20W-50: select by the OEM manual—not by guesswork
The inspection data show clear physical differences. Suitability still depends on the engine design, ambient-temperature chart, operating condition and manufacturer recommendation.
15W-40
Broader cold-grade designationThe lower winter grade and lower measured operating viscosity may suit equipment whose OEM viscosity chart specifies SAE 15W-40.
20W-50
Higher operating viscosityThe higher measured viscosity and HTHS may fit selected engines and warmer-duty recommendations only where SAE 20W-50 is explicitly permitted.
Inspection, handling and publication essentials
What the supplied reports confirm
Both documents identify Shengxiang (Shandong) Energy Technology Co., Ltd. and state a final determination of Pass.
- Measured KV100 values fall inside the stated grade ranges.
- Pour point, flash point, CCS and HTHS results meet the stated report limits.
- No water or mechanical impurities are reported.
- Foaming results are reported as 0/0 for all listed sequences.
Recommended document practice
Keep marketing statements aligned with the authorized product documents and the intended market.
- Use the latest authorized TDS for published typical properties and product claims.
- Use the applicable SDS for safety, first-aid, transport and disposal information.
- Protect containers from water, dust, extreme heat and cross-contamination; keep them sealed and clearly identified.
- Treat 30,000 km as a product-series positioning—not a universal guarantee. Confirm the interval through the OEM schedule, duty severity and oil analysis.
Important questions before selecting CH-4
Can CH-4 be used in every diesel engine?
No. CH-4 is a current API category, but it was created for a specific generation of high-speed four-stroke diesel engines. Use it only when the OEM allows CH-4 and the selected viscosity grade; engines with newer emissions systems may require a later category.
Which grade is thicker at operating temperature?
In the supplied reports, 20W-50 has higher measured kinematic viscosity at 40°C and 100°C and higher HTHS viscosity. This does not mean it is automatically better; the correct grade is the one permitted by the OEM.
Does the -33°C / -34°C pour point mean the engine will start at those temperatures?
No. Pour point is a laboratory low-flow property. Starting performance depends more directly on the specified winter grade, CCS requirements, battery, fuel system and engine condition.
Can the CCS figures be compared directly?
Not as identical-condition results. The 15W-40 value is measured at -20°C, while the 20W-50 value is measured at -15°C. Each should be judged against its own stated limit.
Are these values guaranteed for every production batch?
The supplied documents present measured results for their stated inspection reports. Use the latest authorized TDS for published typical values and the relevant certificate of analysis or inspection report for a specific batch.
Does “30,000 km” guarantee the same drain interval in every vehicle?
No. The supplied documents identify a 30,000 km product series, but the inspection data do not define universal operating conditions or guarantee that interval for every engine. Follow the OEM schedule and adjust only through approved severe-duty guidance and oil analysis.
