Lull 944E-42 Service Manual - Manual (Page 763)

10.5 Model 644E-42/944E-42 Rev. 6/04
Stabil-TRAK™ System
10.2 STABIL-TRAK™ DESCRIPTION
The patented rear axle lock or Stabil-TRAK™ system
works to stabilize the vehicle under various conditions.
The appropriate Owners/Operators manual contains
basic Stabil-TRAK™ information; a copy of the owners/
operators manual should always be available in the
storage compartment located in the pouch on the back of
the seat.
On the operator’s front dash panel (1), the Stabil-TRAK™
locked light (2) goes ON when the Stabil-TRAK™ system
is in the LOCKED mode. The Stabil-TRAK™ slow pivot
light (3) goes ON when the Stabil-TRAK™ system is in
the SLOW PIVOT mode. In this mode the locked light will
be OFF.
The stabilizing system operates via an interface between
the boom proximity switch (4), park brake switch,
stabilizer brake switch and neutral start relay, hydraulic
and electrical circuits, and five solenoid-operated valves
on the Stabil-TRAK™ manifold (5) attached to the
stabilizer cylinder above the left side of the rear axle.
The frame sway cylinder (6) is also involved in the
Stabil-TRAK™ system, but only passively, as hydraulic
oil travels between the frame sway cylinder and the
Stabil-TRAK™ manifold to accommodate Stabil-TRAK™
system operation.
The Stabil-TRAK™ lock system will be activated when
the boom angle is greater than 40° and one or more of the
following functions are activated:
• Engaging the Parking Brake Switch.
• Placing the Travel Select Lever in the (N) NEUTRAL
DETENT position.
• Fully depressing and holding the Service Brake.
With the boom lowered to an angle of less than 40°, the
rear axle lock system is not active and none of these
functions will affect the Stabil-TRAK™ system.
The Stabil-TRAK™ slow pivot system will be activated
when the boom angle is above 40° with the transmission
in gear OR on SN 0160003881 & Before only when the
boom angle is below 40°; with the transmission in gear
and the service brake depressed enough to activate the
system.
0000000
RPM X 100
5
10
15
30
20
25
F
1/2
E 104
176
80
248
120 °C
°F
D
r/min
MU0010 1
2 3
MU4190
4
MU4200
5
MU1110
6