Spicer Tandem Drive Axle Dual Range & Double Planetary 34,000-45,000 lbs - Manual (Page 63)

Dual Range Axle ShiFt Systems
Axle Range Interlock Operation
Engage Lockout (Lock Differential) (Axle in High or Low Range)
Disengage Lockout (Unlock Differential) (Axle in High or Low Range)
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