Extended-drain intervals

A3/B3 for high-performance petrol and diesel light vehicle engines and/or for extended drain intervals where specified by the engine manufacturer and/or for year-round use of low-viscosity lubricants, and/or for severe operating conditions as defined by the engine manufacturer. 

A6/B6 for use at extended drain intervals in high-performance petrol and diesel light vehicle engines designed for low-friction, low-viscosity lubricants with a high-temperature/high-shear rate viscosity of 2.9-3.5 mPa.s. 

Extended-drain intervals, when successfnl, are one way to more efficiently use our petroleum resources. This also results in decreased qnantities of waste oil and less downtime for long-haul diesel trucks. This is not only an environmental benefit, but also an economic benefit for the user. This study evaluates the use of three engine oils formulated for extended-drain use in heavy-duty diesel engines. 

In some cases, the desire to avoid an unnecessary oil change or simply to extend oil drain intervals is an important objective, resulting in reduced lubricant consumption and associated costs. Mission criteria should also influence those machines that should be sampled, the frequency of lubricant analysis, and the types of tests that are conducted. Some machines are more operationally critical than others. They deserve more resources from maintenance technologies. The likelihood that failure will occur and specific challenges (high temperature, risk of contamination, etc.) faced by the lubricant are also factors that influence the type of lubricant analysis and the sampling frequency decision. 

Reduction of diesel exhaust emissions has, in some cases, led to engines producing more soot within the lubricant, exacerbated by extended oil drain intervals leading to more soot-related wear. Some low-emission engines have also experienced increased fuel dilution, causing premature ageing of the lubricant. These issues have presented the lubricant formulator with an array of problems that must be addressed. 

Benz heavy-duty diesel engines. Volvo and Scania, in contrast, have used field testing extensively to predict oil performance and extend oil drain intervals. In these field tests, many parts of the engine are rated, but piston cleanliness tends to be one of the most important rated parameters. 

Improved engine wear protection Extended oil drain interval Excellent cold starting performance Improved fuel economy Reduced oil consumption... 

Dr M Priest (Institute of Tribology, School of Mechanical Engineering, University of Leeds, Leeds, UK). A customer driver for heavy duty diesel engine lubricants is undoubtedly extended oil drain intervals,... 

The general picture is that inside the potential well the distribution has practically the stationary form (6.2), but in the vicinity of the top b it deviates, owing to the draining of probability across the barrier. The rate at which the equilibrium is established is seen from (6.1) to be y. If for a given potential one decreases y, the deviation extends deeper into the well. When it extends beyond the interval where U may be replaced with a parabola the preceding... 

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