Meritor Single Drive Axles
With Traction Equalizer
Some Meritor single drive axles are equipped with a
traction equalizer which is a load sensing, self-
actuating feature. A traction equalizer provides nor-
mal differential action where traction is good. When
one wheel begins to spin faster than the other, clutch
plates in the differential housing automatically en-
gage, delivering power to both wheels. There is no
operator control with this feature.
A traction equalizer occasionally tends to slip in a
jerking motion, producing irregular intervals of sharp
noises. This generally occurs when the vehicle is op-
erating at low speeds on fairly sharp turns. This con-
dition, called slip-stick, is corrected by adding a fric-
tion modifier to the axle lubricant. This additive tends
to reduce the static coefficient of friction to a value
equal to, or lower than, the sliding coefficient.
See Group 35 of the
Century Class Trucks Mainte-
nance Manual
for additional information on friction
modifiers and when to add them to axle lubricants.
CAUTION
Tire sizes on both rear wheels should be the
same on axles equipped with a traction equalizer.
If not, excessive wear may occur in the traction
equalizer.
Meritor Drive Axles With Main
Differential Lock
The Meritor main differential lock is a driver-
controlled traction device operated from the vehicle
cab. A switch allows the driver to lock or unlock the
differential. An indicator light comes on when the dif-
ferential lock is engaged. An optional buzzer can also
be used to indicate differential lock engagement.
The main differential lock provides maximum traction
under slippery conditions. When the differential lock
is engaged, the clutch collar completely locks the
differential case, gearing, and axle shafts together,
maximizing traction of both wheels and protecting
against spinout. Under normal traction conditions, do
not engage the differential lock. Operate the axle
with differential action between both wheels.
WARNING
Be especially careful when driving under slippery
conditions with the differential locked. Though
forward traction is improved, the vehicle can still
slip sideways, causing possible loss of vehicle
control, personal injury, and property damage.
Meritor Main Differential Lock
Operation
To lock the main differential and obtain maximum
traction under slippery conditions, move the control
switch to the lock position.
WARNING
Lock the main differential only when the vehicle
is standing still or moving less than 25 mph (40
km/h). Never lock the main differential when the
vehicle is traveling down steep grades or when
the wheels are slipping. This could damage the
differential or lead to loss of vehicle control,
causing personal injury and property damage.
NOTE: On some vehicles, the differential lock
system is connected through the low speed
range of the transmission. If this system is used,
the transmission must be in the low speed
range for the differential to fully lock.
If the vehicle is moving, maintain a constant vehicle
speed while engaging the differential lock. Briefly let
up on the accelerator to relieve torque on the gear-
ing, allowing the differential to fully lock. The indica-
tor light should come on and the buzzer should
sound on vehicles so equipped. When the differential
is fully locked, the turning radius will increase be-
cause the vehicle understeers. See
Fig. 9.1
. Drive
cautiously and do not exceed 25 mph (40 km/h).
To unlock the main differential, move the control
switch to the unlock position. Briefly let up on the
accelerator to relieve torque on the gearing, allowing
the differential to fully unlock.
NOTE: If the differential lock system is con-
nected through the low speed range of the
transmission, shifting out of low speed range will
also unlock the differential.
Rear Axles
9.1