Use the Correct Oil Grade Specified by Your Manufacturer

The Problem

You use whatever oil is on sale or what the quick-lube shop puts in.

The Hack

Check your owner's manual for the recommended oil grade (e.g., 0W-20, 5W-30). Use exactly this grade at every oil change. Tell the shop specifically if doing it there.

Why It Works

Engine oil viscosity affects internal friction. Using thicker oil than specified increases friction and fuel consumption. Manufacturers engineer engines for a specific grade — using it ensures optimal efficiency.

Pro Tips

• Common modern grades: 0W-20, 5W-20, 5W-30
• The number matters — don't substitute unless approved
• Synthetic oil costs more but lasts longer and flows better
• Wrong grade can also void warranty in some cases