What type of oil for a 5.0 horse power Murray mower?

Murray mowers use a Briggs and Stratton engine, and there are specific recommendations for when to use certain type of oil due to temperature. You can use 10W40 synthetic oil in nearly all normal temperatures. You can use 10W30 if you use your mower during summer and winter months from 6 to 122 degrees Fahrenheit. However, you can also specify your oil usage. For warmer air temperatures (46 degrees Fahrenheit and above) it is recommended to use SAE-30 weight oil. For winter use (below 46 degrees Fahrenheit) it is said, you should use 5W30.