Differential lock theory of operation – Spicer Tandem Drive Axles Service Manual D__R440, 460, 480, D_R461, 462, 463, 521, 581, 601, 651, 652, 653 User Manual
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Wheel Differential Lock
Differential Lock Theory of Operation
The Dana Wheel Differential Lock is an optional feature for
Dana axles. In operation, it positively locks the wheel differen-
tial, power flows to the tires without any differential action,
providing improved traction under adverse road conditions.
The differential lock is driver-controlled through a cab-mount-
ed valve. The locking mechanism is air-operated to engage a
sliding clutch and lock the wheel differential. It is spring-oper-
ated to disengage the lock and permit the wheel differential to
function normally, dividing torque equally between the tires
and compensating normally for cornering or tire size varia-
tions.
The differential lock also includes a selector switch (electric)
which senses clutch engagement and sends an electrical sig-
nal to the cab mounted indicator light (or an audible signal de-
vice).
Do not use your wheel differential lock when traveling down-
hill. Do not use your wheel differential lock at speeds over
25 MPH.
The wheel differential lock consists of three major assemblies
(see illustrations).
•
An air shift unit assembly, which operates a shift fork
and push rod assembly.
•
A shift fork and push rod assembly which engages
and disengages the differential sliding clutch.
•
A sliding clutch is splined to the flange half differen-
tial case which is internally splined.
The differential lock also includes a selector switch (electric),
located on the air shift unit, which senses clutch engagement
and sends an electrical signal to a cab-mounted indicator light
(and/or audible signal device).
WARNING
Parts unique to type 3 differential lock axles.