What Type of Engine Oil is Best for Suffolk County’s Summer Heat?

The number you see on motor oil packaging is a measure of its viscosity.

Oil viscosity affects how the oil flows at different temperatures. There are always two numbers, separated by a dash. 

• The first number combined with a “W” is a measure of viscosity when cold.
• The second is the viscosity at operating temperature. 

It’s not as simple as choosing the most viscous oil possible, because it also needs to match how your car was engineered.  Manufacturers provide a specific rating, or a range, and these should be closely adhered to. You can find this information in your owner’s manual, or ask your auto mechanic in Selden, who has access to an extensive database for all makes and models.

Synthetic oil is better in summer because it is more chemically stable.

• Higher temperatures thin out the oil in your engine, reducing the protective film between moving parts.
• Thinner oil under heavy summer heat can cause increased engine wear.
• When your manufacturer lists a range (such as 5W-20 to 5W-30), the higher number will perform better in sustained summer heat.
• If you choose a full synthetic oil rather than a conventional or synthetic blend, it will resist thermal breakdown, eliminating the need to worry about changing your oil for summer.
• Synthetic oil is more expensive, but the performance and protection are worth it if you want to safeguard your engine from damage and keep it in service for as long as possible.