Top 6 Onan 15W-40 Oil – Motor Oils

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1. Cummins


1 Quart, Cummins 3265336 Onan SAE 15W-40 Oil

Cummins #ad - Reduces consumption and engine wear. Provides maximum protection for engines. Fit type: Universal. 32 oz. Factory tested oil.
BrandCummins #ad
ManufacturerCummins/Onan #ad
Height2.75 Inches
Length9 Inches
Weight1 Pounds
Width4.25 Inches
Part Number3265336

2. Valvoline


Valvoline Premium Blue One Solution SAE 15W-40 Diesel Engine Oil 1 GA

Valvoline #ad - Superior wear protection for hardworking heavy-duty trucks and equipment. Outstanding oxidation resistance supports long oil life in heavy duty engines. One solution technology suitable for a wide range of heavy-duty engines including diesel, gas and natural gas applications. The only one“ endorsed and recommended by Cummins.
BrandValvoline #ad
ManufacturerValvoline #ad
Height10.9 Inches
Length8.2 Inches
Weight7.73 Pounds
Width4.48 Inches
Part Number773780

3. Shell Rotella


Shell Rotella 15W40 Motor Oil Gallon

Shell Rotella #ad - Protects under the most severe engine conditions found in modern low-emission engines and older hard working diesel engines. Increased shear stability for better viscosity control and optimal oil pressure. Exceptional wear protection for longer engine life. Enhanced protection against oxidation for more efficient operation. Superior engine cleanliness for a cleaner engine throughout oil drain interval.
BrandShell Rotella #ad
ManufacturerValvoline Oil Co. #ad
Part NumberOIL50012

4. Shell Rotella


Shell Rotella T6 Full Synthetic 15W-40 Diesel Engine Oil 1-Gallon, Case of 3

Shell Rotella #ad - Case of three 1-gallon bottles with ergonomic design for easy handling and pouring. Exceptional wear protection for longer life in a wide range of heavy-duty engine applications — from pickup trucks to tractors to semi rigs.

Increased shear stability for better viscosity control and optimal engine oil pressure. Multi-functional dispersant additives provide an enhanced level of protection against the effects of soot, dirt, and other contaminants compared to previous formulation. Enhanced fuel economy capability of 1. 5 percent without compromising engine protection or durability compared to 15W-40 oils.

Full synthetic 15w-40 diesel engine oil with Triple Protection Plus technology protects against wear, deposits, oil breakdown, and improves low-temperature flow. Advanced low ash formulation helps protect the exhaust catalysts and particulate filters found on the latest low-emission vehicles. Better cold-cranking properties and low-temperature pumpability for reaching critical engine parts faster.
BrandShell Rotella #ad
ManufacturerRotella #ad
Part Number550050467

5. Lucas Oil


Lucas Oil 10299 SAE 15W-40 CJ-4 Synthetic Motor Oil, 1 Gallon

Lucas Oil #ad - Fit type: Vehicle Specific. Package dimensions: 8. 38 l x 12 h x 3. 5 w inches. Package weight : 7. 8 pounds. Country of Origin : United States.
BrandLucas Oil #ad
ManufacturerLucas Oil #ad
Height12 Inches
Length8.37 Inches
Weight7.58 Pounds
Width3.5 Inches
Part Number10299
WarrantyLimited Manufacturer

6. Shell Rotella T


Case of 3, Shell Rotella T4 Triple Protection Conventional 15W-40 Diesel Engine Oil 1-Gallon

Shell Rotella T #ad - Provides increased shear stability for better viscosity control and optimal engine oil pressure. Triple protection from wear, deposits and oil breakdown, this conventional Diesel Engine Oil provides exceptional wear protection for heavy duty engines for longer life. Formulated with advanced additive technology, which is engineered for superior engine cleanliness throughout the oil drain interval.
BrandShell Rotella T #ad
ManufacturerRotella #ad
Height10 Inches
Length15 Inches
Width6 Inches
Part Number550045126-3PK
Warranty2 year manufacturer