1996 Mercury Grand Marquis Owner's Manual - Page 180

RWARNING To avoid injury, never run the engine with one wheel off the ground, such as when changing a tire. Traction AssistTM (If equipped) Your vehicle may be equipped with the optional Traction AssistTM system. This system helps prevent wheel spin in order to improve tire traction and is an especially useful feature when you drive in hilly areas or on slippery, icy or snowy roads. Traction AssistTM works automatically by rapidly applying and releasing the brakes to prevent one or both of the rear drive wheels from spinning during acceleration. During the Traction AssistTM function, which most often occurs during low speed acceleration on slippery surfaces, a noise may be heard coming from the engine compartment. This noise is created by the ABS pump and is normal and may last for a few seconds during the acceleration of the vehicle. In general, this system improves your vehicle's stability and acceleration performance when road conditions warrant. Traction AssistTM is fully effective up to approximately 25 mph (40 km/h). At 25 mph (40 km/h) the function begins to taper off until it no longer operates above 34 mph (55 km/h). 177