Mack M359 - Front Wheel Hubs; Hubs; Tire Hints; Unitized Front Hubs

MAINTENANCE, LUBRICATION AND SERVICE
TIRES, WHEELS AND HUB
1 Valve Stem
Measure the tread depth. The depth
should not be less than 3.2 mm (4/32-in)
on front tires and not less than 1.6 mm
(2/32-in) on drive tires.
Most premium steer tires start with 14.2
mm (18/32-in) tread depth when new.
Usually remove steer tires at 3.2 mm
(4/32-in). Drive tires should be removed
at not less than 1.6 mm (2/32-in).
It is important to have the wheels
correctly aligned. Check for uneven tire
wear frequently. Uneven tire wear is a
sign of wheels out of alignment.
Tire Hints
Hints on How to Avoid Unnecessary Tire
Wear
• Maintain correct tire pressure
• Check the tire pressure when the tires
are cold
• Check that valve caps are not missing
• Keep the wheels balanced
• Tire wear increases with speed
• Overloading not only decreases tire life
but also creates a hazard
• Incorrect front end alignment causes
increased wear
Dual mounted wheels should always be
of the same type and diameter
(maximum diameter difference allowed
is 6 mm (1/4 in).
Hubs
NOTE
Hub maintenance should be performed by
a certied technician.
Front Wheel Hubs
DANGER
Failure to keep wheel bearings properly
adjusted and lubricated may result in
accelerated tire wear, poor handling and,
in extreme cases, wheel separation from
the hub or from the spindle resulting in
loss of vehicle control and serious
personal injury or death.
Front Wheel Hubs
The front wheel hubs can be lled with
one of several types of oil. Motor oil
should be SAE 30 or 15W40. The oil can
be either petroleum based or synthetic.
Axle oil, API GL-5, SAE 75W-90, can
also be used. There are no set change
intervals for hub lubrication. The only
requirement is that if the hub is opened,
the lubricant must be changed.
Unitized Front Hubs
The non-tapered axle hubs are sealed
with lubricant inside the hub.
Pre-Set Rear Non-Driving Hubs
CAUTION
Do not remove the pre-set rear non-
driving hub sight glass for any reason.
Perform any lubrication rell at the hub
rell plug location. Removing the hub sight
glass will permanently damage the hub.
The hub will have to be replaced if the
sight glass is removed.
To determine if the pre-set rear non-
driving hub requires lubrication, view the
hub lubrication level via the hub front
glass. If lubrication is required, rell is
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