Car engine is the most important part in a car as the heart in your body. You have to feed properly to your car engine for the proper functioning of it. The oil of the car engine of every car has to be changed after every 3000 to 5000 miles. If you do that then you will get the maximum performance from the car even if your car is old for more than 5 years.
Use synthetic oils in your engine as they break down very slowly. Many oils like Castrol, Mobil and others are available in market that uses synthetic technology. Get the servicing work of car regularly in order to get better performance from the car.
Change the oil filter in a regular interval of time. Keep checking oil levels regularly. If you get a trail of oil from the car go to service center immediately and ask for it.