What type & how much lawn mower oil does my engine need?

Before you are able to change the lawn mower oil on your Briggs & Stratton small engine, it’s important to understand the oil type and capacity required. Below we have answered this frequently asked question and explain the two most important steps in understanding your mower better when it comes to lawn mower oil type and capacity.

Choosing the Right Oil Type for Your Small Engine
Oil Capacity for Lawn Mower & Outdoor Power Product Engines

How to Identify the Lawn Mower or Small Engine Oil Type

We recommend the use of Briggs & Stratton Warranty Certified oils for best performance.  Other high-quality detergent oils are acceptable if classified for service SF, SG, SH, SJ or higher.  Do not use special additives.

Outdoor temperatures determine the proper oil viscosity for the engine.  Use the chart to select the best viscosity for the outdoor temperature range expected.  Engines on most outdoor power equipment operate well with 5W30 Synthetic oil.  For equipment operated in hot temperatures, Vanguard 15W50 Synthetic oil provides the best protection.

Lawn Mower Oil Type by Briggs and Stratton

*Below 40°F (4°C) the use of SAE 30 will result in hard starting.

**Above 80°F (27°C) the use of 10W30 may cause increased oil consumption.  Check oil level more frequently.

The Society of Automotive Engineers has developed a categorization of motor oils which will indicate the viscosity (thickness) and temperature in which engine oil can be used. This is called the SAE, it is printed on every bottle of oil and will also indicate whether or not the oil is synthetic.

Above is a chart that lists SAE type and the temperature in which it functions the best. The easiest way to find the best SAE for your lawn mower is to combine information from your operator’s manual with the descriptions of oil types below.

Small Engine Oil Type Recommendations:

  • Use SAE 30 in warmer temperatures of 40° F and higher (5° C and higher)
  • Use SAE 10W-30 for a varying temperature range of 0 to 100° F (-18 to 38° C), this grade of oil improves cold weather starting, but may increase oil consumption at 80° F(27° C) or higher
  • A synthetic oil SAE 5W-30 is the best for very cold temperatures of -20 to as high as 120° F (-30 to 40° C) providing the best protection at all temperatures as well as improved starting with less oil consumption
  • Use SAE 5W-30 for very cold temperatures of 40° F and below (5° C and below)
  • For continuous-use, such as commercial lawn cutting or pressure washing, use Vanguard 15W-50 Oil (temperatures from 20°F to 130°F)

Things to keep in mind when choosing lawn mower oil:

  • Use a high quality detergent oil classified "For Service SF, SG, SH, SJ" or higher.
  • Do not use special additives.
  • Synthetic oils are an acceptable oil at all temperatures. Use of synthetic oil does not alter required oil change intervals.

Can You Use Synthetic Lawn Mower Oil? Yes!

Synthetic Lawnmower Oil by Briggs and Stratton

We have recently modified our engine oil recommendations to state that you may now use a synthetic 5W30 or 10W30 oil in all temperature ranges. We recommend the use of Briggs & Stratton Synthetic Oil. The use of this high quality detergent oil assures compliance with Briggs & Stratton warranty requirements regarding the use of appropriate oil.

Engine break-in procedures using synthetic oil remain the same. Please keep in mind that the use of synthetic oil does not preclude you from performing your regularly scheduled lawn mower maintenance (i.e. check oil, change oil, etc.)

Engine Oil Capacity

Engine oil capacity is, just like oil type, dependent on your specific engine model. To learn how to check the lawn mower oil, please watch our "Checking Engine Oil - Lawnmower Engine"

Outside of the basics regarding oil type & capacity, the best source of information regarding any small engine concern would be a Briggs & Stratton Dealer.