Service Manual User Manual

Section 10
10-70
Model 3606 • Origin 10/99
10.8.16 Stabil-TRAK System
The patented Stabil-TRAK system works to stabilize the
vehicle under various conditions. The
Owners/Operators
Manual
for this vehicle contains basic Stabil-TRAK infor-
mation; a copy of the
Owners/Operators Manual
should
always be in the storage compartment beneath the oper-
ators seat.
The operators display panel Stabil-TRAK indicator (C,
Fig. 10– 47, page 10-48) goes ON when the Stabil-TRAK
system is activated.
The stabilizing system operates via interface among the
boom proximity switch, the park, service brake and travel
select lever switches, and five solenoid-operated valves
on the Stabil-TRAK cylinder manifold.
The front axle frame tilt cylinder is also involved in the
Stabil-TRAK system, but only in a passive role as hydrau-
lic fluid is cycled to accommodate Stabil-TRAK system
operation.
In general, if there is a problem with the Stabil-TRAK sys-
tem beyond common electrical troubles, the involved
electrical and hydraulic circuits should each be checked
and the exact source of the problem diagnosed before
any parts are replaced. Refer to
Section 9 Hydraulic Sys-
tem
in this manual for more information.
The Stabil-TRAK or rear axle lock system can only be
activated when the boom angle is greater than forty
degrees (40° ). Any one, any two or all three of the follow-
ing selections will activate the system:
• Engaging the parking brake switch
• Placing the travel select lever in NEUTRAL (N)
• Depressing and holding the service brake
a. Understanding the Stabil-TRAK system
The following describes the three basic modes of the pat-
ented Stabil-TRAK system. The vehicle may operate in
any one of these three modes.
Free Pivot Mode
(Fig. 10– 82)
Figure 10– 82. Stabil-TRAK system free pivot mode.
With the boom below 40°, the Stabil-TRAK system is in
the free pivot mode and the rear axle is allowed to pivot
freely. The frame sway control will function normally.
Locked Mode
(Fig. 10– 83)
With the boom above 40° and
by activating one or more
of the following functions listed below, the Stabil-TRAK
system is in the locked mode and the rear axle is locked
so it is rigid with the frame.
• engaging the parking brake switch
• placing the travel select lever in NEUTRAL (N)
• depressing and holding the service brake pedal
The frame sway control will function slower than normal
in this mode.
Figure 10– 83. Stabil-TRAK system locked mode.
Final Positioning Mode
(Fig. 10– 84)
With the boom above
40°, the Stabil-TRAK system is
now in the final positioning mode. In this mode the rear
axle is unlocked and is allowed to pivot, but will respond
SLOWLY
to changes in terrain.
The frame sway control function will function normally in
this mode.
IMPORTANT: Regularly check that this system is func-
tioning properly. Refer to the Stabil-Trak System Test Pro-
cedures.
Figure 10– 84. Stabil-TRAK system final positioning mode.
Stabil-TRAK
Light
"OFF"
Below
40°
FREE
PIVOT
MODE
OS0191
Above
40°
LOCKED
MODE
Stabil-TRAK
Light
"ON"
OS1481
Above
40°
Stabil-TRAK
Light
"OFF"
SLOW
PIVOT
MODE
OS1491