New from Lubrication Engineers Inc., Monolec Ultra Syn Heavy Duty Engine Oil is a broad-range multiviscosity synthetic oil for diesel engines that delivers year-round performance, wear protection, fuel efficiency and extended drains.
LE Introduces 5W-40 Synthetic Diesel Engine Oil
New from Lubrication Engineers Inc., Monolec Ultra Syn Heavy Duty Engine Oil is a broad-range multiviscosity synthetic oil for diesel engines that delivers year-round performance, wear protection, fuel efficiency and extended drains

With its synthetic base oil and exclusive additive package, this new SAE 5W-40 formulation reliably lubricates diesel engines, even in low-temperature conditions, without the shear stability and viscosity problems of conventional diesel engine oils, according to the company. Its high viscosity index indicates less change in viscosity over a broad operating temperature range.
Typical applications for Monolec Ultra Syn Heavy Duty Engine Oil include Class 8 tractor-trailers as well as construction vehicles and other off-road mobile equipment.
Benefits of 5W-40 Engine Oil
One of the primary advantages of 5W-40 versus 15W-40 engine oil is better fuel economy. In a controlled lab setting, GM 6.5L dyno testing showed a 1.5% to 1.6% fuel economy improvement for 5W-40 oils over SAE 15W-40 oils.
Extended oil drains, when combined with oil analysis, offer additional cost-saving potential.
In addition, low-viscosity oils are preferred for low-temperature conditions because of their ability to achieve flow quickly during cold startups. However, conventional low-viscosity oils have not always provided adequate oil film at operating temperatures.
The improved technology of LE's Monolec 8854 enables it to achieve flow quickly in cold weather and maintain viscosity at operating temperatures.
Authorized OEM approvals for Monolec Ultra Syn Heavy Duty Engine Oil include but are not limited to: Caterpillar, Cummins, Detroit, Mack, Mercedes-Benz, Renault, and Volvo. Monolec 8854 also provides the necessary protection for modern low-emission engines, per CJ-4 standards.
Available exclusively in LE lubricants, Monolec wear-reducing additive creates a single molecular lubricating film on metal surfaces, increasing oil film strength without affecting clearances, says the company.
Monolec allows opposing surfaces to slide by one another, greatly reducing friction, heat and wear.
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