How many miles does 10-30 synthetic oil last in a 97 Grand Prix?

The recommended oil change interval for a 1997 Pontiac Grand Prix using 10W-30 synthetic oil isn't strictly defined by a mileage number. While synthetic oil generally lasts longer than conventional oil, it's not about miles alone, but also time.

Instead of focusing solely on miles, consult your owner's manual. It will likely recommend oil changes based on either:

* Mileage: A range of miles (e.g., 5,000-7,500 miles) but even this is a general guideline.

* Time: A maximum time interval (e.g., every 6 months) regardless of mileage.

Synthetic oil *can* last longer than conventional oil, perhaps up to 7,500 miles or even 10,000 miles under ideal conditions. However, severe driving conditions (frequent short trips, stop-and-go traffic, towing) significantly reduce this interval. Also, age degrades oil, regardless of mileage.

Therefore, relying solely on a mileage number for synthetic oil changes in a 1997 Grand Prix is risky. Sticking to the recommendations in your owner's manual or consulting a qualified mechanic is crucial for maintaining your engine's health. They can also assess your driving habits to determine a more precise oil change schedule.