freightliner S2 Operator's Manual page 148

transmission. It should not be confused with ex-
haust brake or engine brake. Furthermore, the
grade brake should not be used in place of the
service brakes to stop the vehicle.
Chassis equipped with a propane engine may have
an optional grade brake. The grade brake is de-
signed to downshift the transmission—when going
downhill for example—without overspeeding the en-
gine. Refer to the Allison Operator's Manual for
proper operation of the grade brake. See
for an example of the grade brake switch. An amber
light activates at the top of the switch when the
grade brake is activated.
IGNITION OFF
Park Brake Off
Park Brake On
02/06/2012
Fig. 19.17, Ignition Off (shown when ignition is keyed OFF)
Fig. 19.23
Propane Fuel System
Park Brake On
Headlamps Off &
Ignition On
Marker Lamps Off &
Park Brake On
IGNITION
ON
f040800
19.22