The CRC L-38 Engine Oil Test-Test Number
84-197-07-092
The L-38 is a standard American Petroleum Institute (API) engine oil qualifying test
used for approving all lubricating engine oils that carry the API approval and signage.
This test uses a copper/lead connecting rod bearing with no overlay to represent the extreme in corrosion sensitivity.
This test is run under highly oxidative conditions with a leaded fuel, which stresses the formation of potentially corrosive materials.
Inhibition against peroxide formation is important in passing this test. A formulation, which passes the L-38 test provides a high degree of assurance against bearing corrosion. The L-38 also assess shear stability. The 100° C viscosity of a used oil sample taken at ten (10) hours should remain in the same SAE viscosity grade as the unused oil. Fuel contamination is removed before the viscosity is determined.
According to the American Society for Testing and Materials (ASTM) Method D 5119-95, the test is designed to evaluate an oil “for protection against engine and oil deterioration under high temperature, heavy duty service conditions. The test method can also be used to evaluate the viscosity stability of multi-viscosity oils.” The objective of the test is: “to evaluate a lubricant’s performance in combating copper/lead/tin bearing corrosion and to measure viscous shear stability.”
This test uses a 42.5 CID carbureted, single cylinder, spark ignition, CLR oil test engine. A photo of the L-38 test stand appears above. The engine runs forty (40) hours using a Phillips’ SOLTROL-10 standard leaded iso-octane test fuel. The engine is shut down every ten (10) hours for an oil level check. Engine speed is maintained at 3150 rpm and the oil temperature is raised to 290° F (143° C) using an external oil heater circuit. Fuel contamination from blowby is intentionally introduced and monitored. The actual measurements for rpm’s, oil temperature and blowby are tabulated on page four of the test report. The combination of intentional fuel contamination, high continuous operational speeds and heating of the oil make this a particularly severe test.
If an oil passes this test, it can be assumed to be suitable for API service with regard to bearing corrosion protection and viscosity stability. Other tests need to be carried out to complete the API certification process. Since we are an additive company we have not developed a motor oil for certification, however this test is positive proof whether SFR 100 assists the motor oil chosen or not in improving performance. A formulation which passes the L-38 test cycle, provides the highest degree of assurance against bearing corrosion (chemical wear). The L-38, as the API standard, also assures shear stability of the candidate oil. The L-38 test has been used for some time to qualify engine oils for API service categories starting with API SE. The L-38 has been recently changed and now uses un-leaded fuel, which is not as aggressive on bearing materials as leaded fuel is. Any engine oil formulation currently marketed with the API doughnut or starburst must have passed this test (at least for Society of Automotive Engineers (SAE) grade 5W-30 because the API allows “read across” of the 5W-30 results to other SAE grades). It is important to note that, due to quality variations, some oil formulas, which claim to have passed the test may actually fail if a retail sample is tested through the API audit procedures. SFR’s use of an API licensed retail engine oil sample insures that the results are realistic and representative of quality levels that consumers see.
In this test, an oil must produce no more than 40 mg of total bearing weight loss and the stripped viscosity (measured after fuel contamination is removed or “stripped”) must stay in the viscosity grade range as tested. The commercial motor oil used was Citgo® 10W-40, which is approved at the API SJ performance level as of April 1998 and is rated as producing a 34.6 mg total bearing weight loss according to data kindly provided by Citgo®. When the motor oil was treated with SFR 100 at the suggested rate of 5% by volume, the total bearing weight loss was reduced to 21.8 mg. The data describes a significant improvement of 37% over the untreated oil and fully 45.5% better than the API SJ standard performance requirement of 40 mg. This data demonstrates that, not only is SFR 100 non-corrosive but, it can actually reduce the corrosion that can be caused by even API certified oils for this category.
The ten hour stripped oil viscosity stayed within the test oils SAE viscosity grade. These results support SFR 100’s ability to offer increased protection from corrosive wear even in an extremely severe engine environment without adversely affecting the nominal viscosity of the treated oil. These detailed results were produced by AutoResearch Laboratories Incorporated (ALI) (Chicago, Illinois), which is API and ASTM certified.
These corrosion and viscosity results complement the existing corrosion data in the SFR 100 Technical Data and the viscosity data on the SFR 100 Product Sheet. The test results also show that the oil treated with SFR 100 will not produce deposits in the form of sludge and varnish. A perfect score for cleanliness is 60, SFR 100 treated oil received almost perfect scores of 59.6 for varnish deposits and 58.9 for sludge deposits. The lack of piston and ring deposits and the fine condition of the bearing is apparent from the photographs below. Additional oil analysis testing performed at Cleveland Technical Center (CTC) (Spokane, Washington branch laboratory) determined that the Total Base Number (TBN) of the SFR 100 treated oil ended up at a healthy 6.7 following the demanding test. This TBN represents a decrease of only 0.7 from the untreated reference of 7.4! TBN is the alkalinity reserve provided by an oil which protects against acidic corrosion.

The majority of the printed test report details the control parameters of the test. The test parameters were maintained with the required control limits, which means that the data is valid and usable.
In conclusion, this industry standard report documents that SFR 100 is capable of reducing corrosive wear up to 37% in modern engine oils. This reduction in wear will significantly extend the usable life of bearings and other critical and wear sensitive engine components. This report refutes any concerns that potential customers may have or that may have been raised during sales presentations regarding the corrosion performance of the extreme pressure components of SFR 100. SFR 100’s formulation is optimized for multi-functionality, effectiveness, and safety. Competitive products, which are poorly formulated or optimized for only one function have not proven their corrosion protection performance in this industry standard engine test. Based on the oil analyses that we have done on competitive products, it is possible that many of them would fail if subjected to this test due to a lack of corrosion inhibitors and alkalinity reserve. Competitive products that are particularly viscous or thick may also fail the viscosity requirements of the test.
For a full copy of this report contact
customer_service@sfrcorp.com.
| SFR
100: ASTM-D-5119 L-38 |
 |
| |
A15. Report
Forms
Test Method D5119
L-38 Engine Evaluation of Engine Oils
VERSION 19970129
CONDUCTED FOR
SFR CORPORATION |
 |
| Test
Stand: 84 |
Power
Section |
# of
Runs on Power Section Since Last Ref. |
Total
Runs on Power Section |
| 197 |
07 |
092 |
| Date
Completed: 19980129 |
Completion
Time: 04:30 |
Oil Code SFR
100 |
| Formulation/ CITCO
SUPERGUARD 10W40 OIL BLENDED WITH 5% VOL. SFR 100 |
|
In my opinion this test HAS been conducted in a valid manner in
accordance with Test Method D5119 and the appropriate amendments through
the information letter system. The remarks included in this report
describe the anomalies associated with this test.
The test stand and laboratory have been calibrated in accordance with
the requirements specified in Test Method D5119 and the appropriate
amendment through the information letter system. |
CMIR
or Non-Reference Oil Code |
FIG. A15.1 Operational Validity Statement
-
Reference or Non-reference Oil

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