You must check your owner's manual to determine the correct oil type and viscosity recommended by Pontiac for your specific engine. The manual will specify the weight (like 10W-30, 5W-30, etc.) and the type (conventional, synthetic blend, or full synthetic).
Without knowing the engine size, I cannot give you a definitive answer. Using the wrong oil can severely damage your engine. Always consult your owner's manual.
If you don't have the owner's manual, you can often find a digital version online through Pontiac or General Motors' websites, or through a reputable online parts retailer by entering the vehicle's VIN.
