The best four-stroke engine oil not only protects your vehicle’s engine but also helps your car run more smoothly.
We researched and tested dozens of options, evaluating them on performance, quality, and value. Our top choice, YamaLube All Purpose 4 Four Stroke Oil, offers maximum protection and performance.
Here is the best four-stroke engine oil.
Best Four Stroke Engine Oil: Editor Recommended
Our Editor’s Best Four Stroke Engine Oil Reviews
- Mercury 25W-40 Marine Engine Oil features high-tech, advanced anti-wear additives that provide up to 35% better camshaft wear protect
- Designed to maintain engine reliability and performance, tests have shown that Mercury 25W-40 Marine Engine Oil holds its viscosity ratings longer in industry wear-testing than other oils on the market.
- Mercury Oil, combined with a Mercury Oil Filter will offer optimum marine engine protection.
- NOTE: It is recommended that boat owners change their engine oil annually or as noted in their owners manual.
- High performance Lifan 150cc engine, 1-N-2-3-4 Gear, manual clutch, 4 stroke 4 speed, Shaft size: 17mm
- Replacement / upgrade for XR50 CRF50, Kawasaki KX KLX and other most popular dirt bikes
- This kit comes with engine, starter & gear lever, manifold kit, CDI Box, Ignition coil
- Easy to hook everything up: Just remove your existing engine and reverse the process to put the new one in
- See below Product Description for more specifications
- High performance Lifan 150cc engine, 1-N-2-3-4 Gear, manual clutch, 4 stroke 4 speed
- Replacement and upgrade for XR50 CRF50, Kawasaki and other most popular dirt bikes
- This kit comes with engine, starter & gear lever, manifold kit, CDI Box, Ignition coil
- Easy to hook everything up: Just remove your existing engine and reverse the process to put the new one in
- See below product description for more specifications
- Everything you need for an oil change on all 150hp Mercury and Mariner outboards in one box
- Kit includes (5) 1L bottles of Quicksilver 10W-30 4-stroke Marine Engine Oil, Quicksilver premium oil filter, drain plug seal and drip tray
- Quicksilver 4-Stroke Marine Engine Oil is formulated with advanced corrosion inhibitors and provides outstanding lubricity to reduce wear, scuffing and scoring for improved long-term engine reliability
- Quicksilver oil is certified for use in all leading marine brands
- NMMA FC-W and FC-W Catalyst Compatible
- Everything you need for an oil change on all 40hp through 60hp Mercury outboards in one box
- Kit includes (3) 1L bottles of Quicksilver 25W-40 4-Stroke Marine Engine Oil, Quicksilver premium oil filter, drain plug seal and drip tray
- Quicksilver 4-Stroke Marine Engine Oil is formulated with advanced corrosion inhibitors and provides outstanding lubricity to reduce wear, scuffing and scoring for improved long-term engine reliability
- Special viscosity improvers help to optimize the performance of high-rpm 4-stoke outboards
- NMMA FC-W and FC-W Catalyst Compatible
- Everything you need for an oil change on all 70hp through 115hp Mercury 2.1L outboards in one box
- Kit includes (5) 1L bottles of Quicksilver 10W-30 4-Stroke Marine Engine Oil, Quicksilver premium oil filter, and oil drain hose
- Quicksilver 4-Stroke Marine Engine Oil is formulated with advanced corrosion inhibitors and provides outstanding lubricity to reduce wear, scuffing and scoring for improved long-term engine reliability
- Quicksilver oil is certified for use in all leading marine brands
- NMMA FC-W and FC-W Catalyst Compatible
- 【PROFESSIONAL ENGINE KIT】This engine is a 4-stroke motor engine kits, includes everything a motor needs at a economic price, fits normal 28'' V frame bike and 26'' ATV bike , both with 28mm-40mm (1''-1.6'') frame tube.
- 【HIGH PERFORMANCE MOTOR】This 4-stroke motor is more stable, more reliable and quieter than the 2 stroke rivals, with powerful motor and 44 tooth 9 hole sprocket, this motor is with speed 27-32 MPH / or 43-51 KPH, with 41.8mm x 36mm (1.65'' x 1.42'') bore stroke, 49cm³/3 cu in displacement, oil tank capacity 2.5liter/85oz.
- 【MAIN PARAMETERS 1】Engine model: 142F, Engine type: Air-cooled, 4-Stroke, OHV, single cylinder, Bore x Stroke: 41.8mm x 36mm (1.65'' x 1.42''), Displacement: 49cm³ (3 cu in), Compression ratio: 8:1, Net horse power output: 1.6KW/2.1HP at 7000RPM, Net torque: 2.7NM/2lbf at 4500RPM, PTO shaft rotation: Counterclockwise (from PTO shaft side).
- 【MAIN PARAMETERS 2】Ignition system: Transistorized magneto ignition, Starting system: Recoil starter, Carburetor float type, Lubrication system: Forced splash, Governor system: Centrifugal mechanical, Air cleaner semi-dry type Oil capacity (for luburati oil): 0.25 liter / 8 oz Fuel tank capacity: 0.77 liter / 26 oz, Package size: 53cm x 29cm x 29cm (21'' x 11'' x 11''), Shipping weight: 13.75kg/30lb.
- 【PACKAGE CONTENTS】1 x Engine; 1 x Gas tank, Plastic gasoline fuel line, fuel value; 1 x Adjustable chain idler; 1 x 44 tooth 9 hole sprocket;1 x Chain guard; 1 x Extra wide crank/sprocket; 1 x Fiber sprocket mounting rings, 9 sprocket bolts, 3 metal retaining segments; 1 x Engine Mounting plate with universal mounting brackets; 1 x Spark Plug Wrench; 1 x Misc.mounting bolts with nuts; 1 x Heavy duty #415 chain; 1 x Twist grip throttle with built-in kill switch; 1 x Adjustable throttle cable.
- Everything you need for an oil change on all 175hp through 300hp 4-stroke Mercury V6 and V8 outboards in one box
- Kit includes (7) 1L bottles of Quicksilver 10W-30 4-Stroke Marine Engine Oil, Quicksilver premium oil filter, drain plug seal and funnel
- Quicksilver 4-Stroke Marine Engine Oil is formulated with advanced corrosion inhibitors and provides outstanding lubricity to reduce wear, scuffing and scoring for improved long-term engine reliability
- Quicksilver oil is certified for use in all leading marine brands
- NMMA FC-W and FC-W Catalyst Compatible
Best Four Stroke Engine Oil Buying Guide
1. By Application: The first step is to determine the application of the engine you are choosing from by looking at the following points:
a. Air-cooled or water-cooled: An air-cooled engine is one whose cooling system is not immersed in liquid. These are the most widely used two-stroke engines and are generally found in small-scale applications. Water-cooled engines are the ones that are immersed in liquid and heat is dissipated through the liquid.
b. Stationary or portable: The next step is to determine whether the engine you are choosing is meant for stationary or portable use. The difference lies in the mounting points of the engine.
A portable engine has mounting points that are designed to allow it to be transported easily. On the other hand, the stationary engine has no such points, which means it cannot be moved.
c. High- or low-power: The next step is to determine the intended use of the engine so that you can choose one that meets your requirements.
If it will be used for heavy-duty applications, you need to choose an engine that is more powerful. On the other hand, if it will be used in light-duty applications, you can choose a smaller engine.
d. Single- or multiple-cylinder: If you are choosing a multiple-cylinder engine, it is important to determine the number of cylinders and their configuration.
An engine can have either in-line or opposed configurations. An in-line configuration has the cylinders aligned along a single axis, while in an opposed configuration, the cylinders are arranged in a V shape.
e. Reciprocating or rotary: The next step is to determine the type of motion of the engine you are choosing. A reciprocating engine, also known as a ‘piston’ engine is the most common type of engine.
It has a crankshaft at the center with connecting rods and a connecting rod with a piston. On the other hand, a rotary engine is one where the crankshaft is fixed with the engine housing.
There are two types of rotary engines: single-phase and two-phase. In a single-phase rotary engine, there is only one single rotor, while in a two-phase rotary engine there are two rotors and they rotate in opposite directions.
What else you should know about the best four-stroke engine oil
1. What are the benefits of using a four-stroke engine oil?
Four-stroke engine oil is designed to lubricate the engine, protect it from corrosion, and help to keep it clean. It also helps to improve fuel economy and reduce emissions.
2. What are the best brands of four-stroke engine oil?
The best brands of four-stroke engine oil include Castrol, Valvoline, and Mobil 1.
3. What are the differences between four-stroke engine oils?
The main difference between four-stroke engine oils is their viscosity or thickness. Thicker oils provide more protection for engine parts, while thinner oils allow the engine to run more efficiently.
4. How do I choose the best four-stroke engine oil for my vehicle?
The best four-stroke engine oil for your vehicle is determined by the manufacturer’s specifications.
5. What are the most common problems associated with four-stroke engine oils?
The most common problems associated with four-stroke engine oils are poor lubrication, sludge build-up, and oil leaks.
Conclusion
On the market, there is numerous best four-stroke engine oil. Hopefully, the list of the top ten best four-stroke engine oil will save you time researching and deciding on the best one for you.