Freightliner Business Class. Manual - part 26

Flush the unit with clean flushing oil, then drain it
completely.

IMPORTANT: Do not flush axles with solvent,
such as kerosene.

Clean the drain plugs. For magnetic drain plugs,
a piece of key stock or any other convenient
steel slug may be used to short the two magnetic
poles and divert the magnetic field.

NOTE: Meritor recommends using magnetic
plugs with elements having a minimum pickup
capacity of 2 pounds (1 kg) of low-carbon steel,
in plate or bar form. Magnets will rapidly lose
effectiveness as collected material bridges the
gap between the two poles. Clean or change
the plugs before this occurs. It may be neces-
sary to clean or change the plugs one or more
times between lubrication change intervals.

After cleaning the drain plugs, install and tighten
them 35 lbf·ft (47 N·m).

Axle Filling

With the vehicle on a level surface, fill the axle
housings to the bottom of the oil fill hole (in the
carrier or housing) with lubricant. See

Table 1

for

approved axle lubricants and see

Table 2

Table 3

for axle capacities.

NOTE: Meritor axles have a small tapped and
plugged hole located near and below the hous-
ing oil fill hole. This smaller hole is for the lubri-
cant temperature sensor only, and must not be
used as a fill or level hole.

Install the fill hole plug, and tighten it 35 lbf·ft (47
N·m).

After filling the carrier and housing assembly with
lubricant, drive the vehicle, unloaded, for 1 or 2
miles (2 or 3 kilometers) at speeds not to exceed
25 mph (40 km/h), to thoroughly circulate the
lubricant throughout the assembly.

35–04 Two-Speed-Axle Shift

Unit Oil Level Checking

CAUTION

Failure to keep lubricant at the specified level
could cause damage to the axle shift unit.

Clean the oil fill hole plug in the shift unit housing
cover, and the area surrounding it. See

Fig. 2.

Remove the fill hole plug.

The lubricant level should be maintained at the
bottom of the fill hole. If low, add the specified
lubricant.

CAUTION

Before adding additional lubricant, make sure
what type is currently in the axle shift unit. Do not
mix engine oil and automatic transmission fluid,
to prevent component damage.

f350021a

08/06/93

Housing Cover Gasket

Oil Fill Hole Plug

Shift Unit Housing Cover

Fig. 2, Two-Speed-Axle Shift Unit

Rear Axle

Business Class Trucks Maintenance Manual, January 1998

35/3

kerosene to three parts of SAE 10 heavy-duty
engine oil, API service classification SD (sul-
fated ash content must not exceed 1.85%). This
cold-weather mixture can be safely used up to
32°F (0°C).

Commercially available automatic transmission
fluid may be used in place of SAE 10 engine oil.
Automatic transmission fluid can be used for all
temperatures. Do not mix kerosene with auto-
matic transmission fluid.

Apply a small amount of Loctite

242, or equiva-

lent sealant, to the threads of the fill hole plug.
Install the fill hole plug finger-tight; then, using a
wrench, tighten the plug 1-1/2 turns more.

35–05 Two-Speed-Axle Shift

Unit Oil Changing

Remove the shift unit housing cover (

Fig. 2

), and

drain the old lubricant. Discard the housing cover
gasket, and the old lubricant.

Thoroughly wash the axle shift parts and housing
cover, and allow them to air dry.

Install the housing cover and a new housing
cover gasket. Tighten the housing cover cap-
screws 90 to 110 lbf·in (1020 to 1240 N·cm),
then remove the oil fill hole plug from the cover.

Fill the shift unit housing through the oil fill hole
until the specified lubricant is level with the bot-
tom of the opening.

IMPORTANT: When the vehicle operating tem-
peratures are above 0°F (–18°C), use SAE 10
heavy-duty engine oil, API service classification
SD (sulfated ash content must not exceed
1.85%). When the vehicle operating tempera-
tures are below 0°F (–18°C), use one part of
kerosene to three parts of SAE 10 heavy-duty
engine oil, API service classification SD (sul-
fated ash content must not exceed 1.85%). This
cold-weather mixture can be safely used up to
32°F (0°C).

Apply a small amount of Loctite 242, or an
equivalent sealant, to the threads of the oil fill
hole plug. Install the oil fill hole plug finger-tight;
then, using a wrench, tighten the plug 1-1/2 turns
more.

Rear Axle

Business Class Trucks Maintenance Manual, January 1998

35/4

Title of Maintenance Operation (MOP)

MOP Number

Wheel Nut Checking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40–01

Wheels and Tires

Index, Alphabetical

Business Class Trucks Maintenance Manual, January 1998

40–01 Wheel Nut Checking

IMPORTANT: In addition to the maintenance
interval in this manual, check the wheel nut
torque the first 50 to 100 miles (80 to 160 km)
of operation after a wheel has been removed
and installed.

When checking wheel nuts on a dual disc assembly,
remove one outer nut at a time, tighten the inner nut,
then reinstall the outer nut. Repeat this procedure for
all of the inner wheel nuts in the sequence shown in

Fig. 1

, then tighten all of the outer wheel nuts in the

same sequence.

CAUTION

Too little wheel nut torque can cause wheel
shimmy, resulting in wheel damage, stud break-
age, and extreme tire tread wear. Too much wheel
nut torque can break studs, damage threads, and
crack discs in the stud hole area.

See

Table 1

Table 2

, or

Table 3

for wheel nut

torque specifications, and see

Fig. 1

for the tighten-

ing sequence.

Fastener Torque for 10-Hole Disc Wheel

With Inner and Outer Locknuts

Description

Nut Size

Wheel

Manufacturer

Torque (dry threads)

lbf·ft (N·m)

Front Wheel Nut

3/4–16, 1-1/8–16

Accuride

450–500 (610–680)

Rear Wheel Inner Nut

3/4–16

Accuride

450–500 (610–680)

Rear Wheel Outer Nut

1-1/8–16

Accuride

450–500 (610–680)

Wheel Stud Retainer Nut

3/4–16

Accuride

175–200 (235–270)

Table 1, Fastener Torque for 10-Hole Disc Wheel With Inner and Outer Locknuts

Fastener Torque for 8-Hole Disc Wheel

With Cone Locknuts

Description

Nut Size

Torque (lubricated threads)

lbf·ft (N·m)

Front and Rear Wheel Nuts

M20

280–310 (380–420)

Table 2, Fastener Torque for 8-Hole Disc Wheel With Cone Locknuts

Spoke-Type Wheel Fastener Torque

Description

Size

Wheel

Manufacturer

Torque (dry threads)

lbf·ft (N·m)

Front Wheel Nut, 5- and

6-Spoke

3/4–10

Gunite

200–225 (270–305)

Rear Wheel Nut, 5- and
6-Spoke With Channel Spacer
(

Fig. 2

)

3/4–10

Gunite

200–225 (270–305)

Rear Wheel Nut, 5- and
6-Spoke With Corrugated
Channel Spacer (

Fig. 3

)

3/4–10

Gunite

240–260 (325–350)

On front axles with over 12,000 lbs (5448 kg) capacity, tighten the wheel nuts 240 to 265 lbf·ft (325 to 359 N·m).

Gunite part number W–854 nut with a phosphate and oil coating must be used.

Table 3, Spoke-Type Wheel Fastener Torque

Wheels and Tires

Business Class Trucks Maintenance Manual, January 1998

40/1

Content .. 24 25 26 27 ..