Normal Noises and Feel

PEDAL FEEL
In general, pedal feel will be similar to that of a conventional vacuum boosted brake system. Under certain conditions the pedal may drop slightly when there is a need for pressure increase during a long antilock stop. Remember, the sequence of antilock events is to isolate, decrease and then increase pressure to maintain brake effectiveness. At the point when the system is in the increase mode is when the pedal will drop slightly.

TIRE NOISE AND MARKS
Although the Rear Wheel Antilock brakes (RWAL) system prevents complete rear wheel lock-up, some wheel slip is desired to obtain optimum braking performance. During brake pressure modulation brake pressure is increased and wheel slip controlled by the Controller Antilock Brake (CAB) is allowed to reach up to approximately 20%. This means that the wheel rolling speed is approximately 20% less than that of a free rolling wheel at any given vehicle speed. The wheel slip may result in some tire "chirping", depending upon the road surface. This sound should not be interpreted as a total wheel lock-up and can be considered normal under most conditions. Complete wheel lock-up normally leaves a continuous black tire mark on dry pavement. Antilock braking will not leave a continuous black mark since the wheel never reaches a totally locked condition. Tire marks may be noticeable as light, patched marks on the pavement.

SOUND LEVEL
The noise level of antilock braking is different from normal braking. The noise level of a vehicle equipped with ABS actually may be less during antilock braking. Because the rear wheels never fully lock-up, which would cause tire noise. Also, since the RWAL brake system has no pump to produce noise that might be associated with other antilock brake systems, RWAL's ABS mode will be noticeably different.