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Heavy-Duty Synthetic Blend Motor Oil 15W-40

Made for the most demanding on-road and off-road diesel applications.

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PEAK® Synthetic Blend Diesel Engine Oil is as tough as the vehicles and environments in which they operate. PEAK® 15W-40 CK-4/SN Synthetic Blend Diesel Engine Oil is designed to deliver on performance in four key areas:

  • Resistance to oil oxidation and high temperature volatility – major contributors to oil viscosity breakdown
  • Premium shear stability control – longer oil life and wear protection.
  • Oil aeration, Sludge and carbon deposit reduction
  • Low temperature pumpability – quick oil circulation for immediate engine protection at start-up.



PEAK® Synthetic Diesel Engine Oil meets the latest manufacturer’s requirements for 2017 and previous model year on-road and off-road diesel fueled applications


Recommended for maximum protection in high-performance, low-emission diesel, and turbo-diesel engines equipped with EGR (Exhaust Gas Recirculation), Diesel Particulate Filters and SCR (Selective Catalytic Reduction) systems.


Specifications Approvals:

Meets API CK-4, CJ-4, CI-4 PLUS, CI-4, CH-4/SN, SM, SL, SJ, ACEA E9-2012, E7, MACK/VOLVO EOS-4.5, EO-O Premium Plus, EO-O, VDS 4.5, VDS-4, VDS-3, CATERPILLAR ECF-3, ECF-2, CUMMINS CES 20086, CES 20081, DETROIT DIESEL DFS 93K222, 93K218, DAIMLER MB 228.31, MAN M3575, MTU CATEGORY 2.1 and RENAULT RLD-4, RLD-3



Made for the most demanding on-road and off-road diesel applications.

Our complete selection of PEAK® Motor Oils are formulated with high-quality petroleum base stocks and fortified with advanced additive technology. These advanced additives are consumed by the vehicle’s engine over the course of the oil’s lifespan or drain period. As the oil performs its job of trapping combustion’s harmful by-products it gradually becomes less efficient and effective. That’s why oil must be changed on a regular schedule and why an oil change is one of the most important, and easiest, vehicle maintenance tasks.

Made for the most demanding on-road and off-road diesel applications.

Limited Warranty In the unlikely event that a PEAK® Motor Oil customer suffers vehicle component damage as a result of the use of a PEAK® Motor Oil product, Old World Industries, LLC. (“Old World”) will pay the cost of necessary repairs (subject to the maximum claim amount set forth below) provided that the PEAK® Motor Oil product was used as recommended by the vehicle manufacturer and by Old World and that the damaged component was maintained in accordance with the manufacturer’s recommendations. Proof of proper maintenance of the damaged component and use of the PEAK® Motor Oil product will be required. Customers who claim to have suffered vehicle component damage as a result of the use of a PEAK® Motor Oil product must provide a sample of the PEAK® Motor Oil product actually used in the damaged vehicle component for testing purposes. Any damaged vehicle component must be available for inspection. This limited warranty (“Warranty”) is the only express warranty that applies to PEAK® Motor Oil products and sets forth all of the obligations and responsibilities of Old World. Any and all applicable implied warranties are limited to the terms, conditions and duration of this express Warranty. All other warranties, express or implied, are specifically disclaimed. Old World shall not be responsible or liable for any amount of damage in excess of an approved repair estimate (in Old World’s sole discretion) and in no event will any claim payment be made in an amount exceeding $1,000.00. Incidental, consequential, special or punitive damages, including any claims for lost profits, are specifically excluded from coverage under this Warranty. STATE LAW RIGHTS: THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE. SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION OR EXCLUSION MAY NOT APPLY TO YOU.