DESCRIPTION AND USE OF OPERATOR'S CONTROLS
AND INDICATORS - CONTINUED
INSTRUMENT PANEL - CONTINUED
Upper Right Dash Panel.
Control or Indicator
Vents air into cab from heater/ventilator/defroster
Engine (Jake) Brake
Select number of engine cylinders desired for braking
action (two, four, or six cylinders). Turn on left switch
for two cylinders, right switch for four cylinders, and
both switches for all six cylinders.
Fifth Wheel Slide
Permits repositioning of sliding fifth wheel from inside
cab. LOCK position deactivates control valve and
locks fifth wheel to baseplate. UNLOCK position
activates control valve to allow changes to total
length of tractor-trailer and changes to axle loads.
Control Valve Lever
Locks and unlocks driveline based on changing
LOCK. In poor traction conditions, stop vehicle
and place lever in LOCK position to lock up
UNLOCK. When conditions are back to normal,
move lever to UNLOCK while vehicle is moving.