MOTOR TRUCK SERVICE MANUAL
AXLES-REAR
Maintenance
TANDEM LOCK
The NoSPIN locking type differential can also be used in
The disassembly, cleaning, inspection and repair of the
place of the conventional interaxle differential and lock-
tandem lock is the same as covered previously for the
out control in tandem axles, Fig. 12. In this capacity it
single axle unit. For removal and installation of the inter-
operates between the axles in the same manner as
axle differential, see specific instructions for the
between the wheels of a single axle. When the "Tandem
conventional unit covered in the Service Manual,
Lock" (its name for this application) is used in the power
Tandem Axle, Section R (CTS-2164).
divider unit, the need for manual control of the interaxle
differential lockout is completely eliminated.
IMPORTANT PRECAUTION
Operation
Inter-axle differential action is required when cornering to
If a truck is equipped with a NoSPIN differential, power
permit forward tandem axle to travel farther and faster
will be transmitted to the opposite rear wheel or axle if
than rear tandem axle. The tandem lock inter-axle
one of the rear wheels or axles slips. Both rear wheels
differential, mounted on forward end of thru shaft, allows
or both rear axles must be raised free of ground if it is
either drive axle to turn faster than driven speed but does
necessary to operate one rear wheel with truck
not permit either axle to turn slower than driven speed
stationary; otherwise, the wheel or axle that is not raised
when power is applied. A right or left turn in a forward
will pull truck off its support.
direction disengages front driven clutch (b) and side gear
(a) from the drive teeth of central driver or spider (c).
This results from the wheels on forward tandem axle
LUBRICATION
covering a greater arc than those on rear axle, and
driven by traction of road they rotate faster than driven
speed.
The NoSPIN unit is lubricated with the same lube used in
conventional differentials. Fill differential carrier through
In like manner the rear driven clutch (d) tries to rotate
filler hole until oil is level with hole. For tandem axles be
slower than central driver (c), but design prevents this.
sure to pour one (1) pint of lube into power divider
Torque is then transmitted through rear side gear (e) of
through hole on top of interaxle differential cover. Check
tandem lock unit to rear tandem axle at driven speed to
level at each chassis lubrication. Fill as necessary.
propel the vehicle. This automatic, fulltime power control
minimizes tire scuffing and axle shock loads. It also
Drain differential carrier every 25, 000 miles or once a
eliminates possible mechanical failure through driver
year.
error in the incorrect use of a manual inter-axle lockout.
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