Search Results

Under “real life” conditions, the differences between conventional 10W-40 oils and several 10W-40 oils formulated for fuel economy were small. Furthermore, such differences would be difficult for the individual consumer to detect as a result of other variables such as changes in driving patterns and the effect of seasonal temperature changes.

A fuel-efficient passenger car engine oil has been developed that showed an average of 4.6% improvement in fuel economy compared with several premium, SAE 10W-40 oils (API Engine Service Classification SE) in a road fleet test. In the combined Environmental Protection Agency city/highway testing, this oil gave 5.5% better fuel economy on average than an SE premium 10W-40 oil. ...In the combined Environmental Protection Agency city/highway testing, this oil gave 5.5% better fuel economy on average than an SE premium 10W-40 oil. The excellent overall performance of this lubricant was confirmed by ASTM Engine Sequence tests and evaluation in severe taxicab operations. ...The new 10W-40 oil, which incorporates friction-reducing properties, is formulated with petroleum base stocks and known additives, many of which are conventionally used.

“True” SAE 10W-40 products can be made, where measured SAE 10W performance is obtained together with shear stability characteristics which enable the oil to remain in the SAE 40 viscosity range even after service in normal passenger car engines. ...“True” SAE 10W-40 lubricants provide oil economy characteristics significantly superior to those afforded by conventional SAE 10W-30 and SAE 10W-40 oils, and equal the performance of available SAE 20W-50 oils, while also offering excellent low temperature cranking and starting ability. ...“True” SAE 10W-40 lubricants provide oil economy characteristics significantly superior to those afforded by conventional SAE 10W-30 and SAE 10W-40 oils, and equal the performance of available SAE 20W-50 oils, while also offering excellent low temperature cranking and starting ability.

Bench oxidation and wear data and engine performance of 5W-30 and 10W-40 motor oils formulated with conventionally refined and special basestocks are compared.

Comparative automobile field tests in private commuter, taxicab, and highway service are shown for both SAE 10W-30 and a carefully compounded SAE 10W-40 oil. Observations of cylinder and piston ring wear, crankcase deposits, PCV valve cleanliness, and oil economy are reported.

An SAE 10W-40 high quality part-synthetic heavy duty diesel engine oil was found to generate over 20% less particulate matter than two fully synthetic products of higher performance specification (SAE 5W-40 and 10W-40), whereas the fully synthetic oils showed a 10% reduction in Nox. ...An SAE 10W-40 high quality part-synthetic heavy duty diesel engine oil was found to generate over 20% less particulate matter than two fully synthetic products of higher performance specification (SAE 5W-40 and 10W-40), whereas the fully synthetic oils showed a 10% reduction in Nox. All three oils are commercially available.

Whereas reduced viscosity multigrade oils did not show significant benefits over a commercial type SAE 10W-40 proposal S-1 oil, those same reduced viscosity multigrade oils containing colloid friction modifier demonstrated consistent and statistically significant improvements in fuel economy over that commercial oil. 4. ...Incorporation of colloid friction modifier in a single grade (SAE 30) oil produced consistent and statistically significant improvements in fuel economy over the commercial type SAE 10W-40 oil. Statistically valid improvements in fuel efficiency due to the presence of colloid friction modifier can be observed in this data in the general range of five to ten percent.

Popular SAE 10W-40 and 5W-50 oils formed more deposits because they contain VI improvers. Deposit weight correlated directly with oil shear stability which is a measure of the VI improver quality.

Special attention is given to the SAE 5W-30 viscosity grade in comparison to the widely marketed SAE 10W-40 grade product.

However, tests on four oils which met the SAE multiviscosity engine oil classification (three SAE 10W-30 and one SAE 10W-40) showed that the low shear rate viscosity of these oils could not be used to predict the bearing oil film thickness developed by these oils.

In GM City-Suburban and 80 km/h constant-speed tests conducted at the Indianapolis Motor Speedway, fuel economy with low-viscosity engine oil and rear axle lubricant combinations was about 1 to 2 percent greater than that with SAE 10W-40 engine oil and SAE 80W-90 rear axle lubricant. These improvements were obtained after 40 000 and 80 000 km of taxicab service. ...Fuel economy with a graphite-containing SAE 10W-40 engine oil was about 2.5 percent better in both tests. No differences in either engine or rear axle durability were observed among the lubricants. ...However, oil economy with low-viscosity engine oils was about 20 to 30 percent less than that with the SAE 10W-40 oil. Adding either graphite or MoS2 to an SAE 5W-30 engine oil did not affect oil economy or oil performance, but oil filter plugging was increased in high-mileage cabs.

The ABINGDON 1-J test has been used to evaluate both 5W30 and 10W40 oils of Super High Performance Diesel quality. Performance of both mineral and synthetic basestocks are considered.

This paper presents experimental measurements of oil film thickness for a statically loaded journal bearing with single-grade, polymer-free engine oils and SAE 10W40 polymer-containing engine oils under hydrodynamic lubrication conditions. Measured minimum film thickness was correlated with a bearing Sommerfeld number based on actual high shear rate viscosities with no significant difference being observed between polymer-free and polymer-containing oils.

For multigrade oils (SAE 5W-30, 10W-30, 10W-40, and 15W-40) MOFT values could not be related to the Sommerfeld number with a high degree of correlation.

The viscosity of 10W/40 motor oils formulated with different viscosity index (VI) improvers has been measured at pressures up to 200 MPa (2000 bar) over a wide temperature and shear rate range.

Viscosity losses are also reported for a variety of commercial 10W-40 grade service station engine oils, when tested by this procedure.

These oils, SAE 10W-40 grades, were run in high mileage or turnpike service, as well as surburban service. The performance with unleaded fuels was not significantly different from that for leaded fuels in the areas of wear, sludge, varnish, or rust.

Rheological studies of an SAE 10W-40 motor oil were made over temperature and shear rate ranges typical of service. These include evaluations of both new and used oils.

Two monograde oils (API CC), 10W and 40, and three multigrade oils (two 10w-40 oils; API SF, ACEA B3-98 and API SL/CF, ACEA A3/B3; and a 15W-40 oil; API SL/CF, ACEA A2/B2) were tested. ...Over the same temperature range, the tensile strengths of the 10W-40 multigrade oils were found to be comparable to the 10W oil Fc at 25°C and tend towards the 40 oil Fc value at 110°C.

However, for a number of polymer-containing oils including 10W30 and 10W40 multigrades, similar experiments showed that wear was not influenced by high-shear viscosity at least not in the region between 2.1 and 4.9 mPa.s.