Control of a VehicleYou have three systems that make your vehicle gowhere you want it to go. They are the brakes, thesteering, and the accelerator. All three systemshave to do their work at the places where the tiresmeet the road.Sometimes, as when you are driving on snow orice, it is easy to ask more of those control systemsthan the tires and road can provide. That meansyou can lose control of your vehicle. See TractionControl System (TCS) on page 323 andStabiliTrak® System on page 326.Adding non-GM accessories can affect yourvehicle’s performance. See Accessories andModifications on page 363.BrakingSee Brake System Warning Light on page 248.Braking action involves perception time andreaction time.First, you have to decide to push on the brakepedal. That is perception time. Then you have tobring up your foot and do it. That is reaction time.Average reaction time is about three-fourths of asecond. But that is only an average. It might be lesswith one driver and as long as two or three secondsor more with another. Age, physical condition,alertness, coordination, and eyesight all play a part.So do alcohol, drugs, and frustration. But even inthree-fourths of a second, a vehicle moving at60 mph (100 km/h) travels 66 feet (20 m). Thatcould be a lot of distance in an emergency, sokeeping enough space between your vehicle andothers is important.And, of course, actual stopping distances varygreatly with the surface of the road, whether it ispavement or gravel; the condition of the road,whether it is wet, dry, or icy; tire tread; thecondition of the brakes; the weight of the vehicle;and the amount of brake force applied.320
