5.4 – Using Air Brakes 5.4.1 – Normal Stops Push the brake pedal down. Control the pressure so the vehicle comes to a smooth, safe stop. If you have a manual transmission, don't push the clutch in until the engine rpm is down close to idle. When stopped, select a starting gear. 5.4.2 – Braking with Antilock Brakes When you brake hard on slippery surfaces in a vehicle without ABS, your wheels may lockup. When your steering wheels lockup, you lose steering control. When your other wheels lockup, you may skid, jackknife, or even spin the vehicle. ABS helps you avoid wheel lockup. The computer senses impending lockup, reduces the braking pressure to a safe level, and you maintain control. You mayor may not be able to stop faster with ABS, but you should be able to steer around an obstacle while braking, and avoid skids caused by over braking. Having ABS on only the tractor, only the trailer, or even on only one axle, still gives you more control over the vehicle during braking. Brake normally. When only the tractor has ABS, you should be able to maintain steering control, and there is less chance of jackknifing. But, keep your eye on the trailer and letup on the brakes (if you can safely do so) if it begins to swing out. When only the trailer has ABS, the trailer is less likely to swing out, but if you lose steering control or start a tractor jackknife, letup on the brakes (if you can safely do so) until you gain control. When you drive a tractor-trailer combination with ABS, you should brake as you always have. In other words Use only the braking force necessary to stop safely and stay in control. Brake the same way, regardless of whether you have ABS on the tractor, the trailer, or both. As you slowdown, monitor your tractor and trailer and back off the brakes (if it is safe to do so) to stay in control. There is only one exception to this procedure, if you always drive a straight truck or combination with working ABS on all axles, in an emergency stop, you can fully apply the brakes. Without ABS, you still have normal brake functions. Drive and brake as you always have. Remember, if your ABS malfunctions, you still have regular brakes. Drive normally, but get the system serviced soon.