Final answer:
When descending a steep grade in a standard transmission car, use engine braking by shifting to a lower gear to use the engine's resistance to slow down the car, helping prevent brake system overheating and maintaining control.
Step-by-step explanation:
When driving down a steep grade in a car with a standard transmission, it's essential to use the engine's braking power to help control the vehicle's descent. This method is known as engine braking. To do this, you should shift into a lower gear to increase the engine rpm, which, in turn, provides resistance through the drivetrain and slows down the car. This action reduces the reliance on the brake system, which can overheat during prolonged application, especially on long descents. You should always stay in control of the vehicle, maintain a safe speed, and be aware of road conditions that may affect traction, such as dry concrete, wet concrete, or ice.