Service Manual D__R440, 460, 480, D_R461, 462, 463, 521, 581, 601, 651, 652, 653 Owner manual

110
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.