Freightliner Century Class. Manual - part 23

driver’s manual. Meritor’s experience shows that the
following additives (friction modifiers) perform ad-
equately:

A. For all synthetic gear oils other than Mobil, add

1.6 ounces (35 mL) of additive for each pint (0.5
L) of lube capacity:

• Elco No. 2 Friction Modifier (Elco Corpora-

tion).

• Lubrizol No. 6178 (Lubrizol Corporation).
• Hi-Tec E-336 (Edwin Cooper, Inc.).
• Equa-Torque No. 2411 (Sta-Lube Corpora-

tion).

• Equa-Torque No. 2414 (Sta-Lube Corpora-

tion).

B. For Mobilube SHC (synthetic) use Mobil No. 204

(Mobil Oil Corporation). Add 1.1 ounces (23 mL)
of additive for each pint (0.5 L) of lube capacity.

IMPORTANT: These friction modifiers generally
deteriorate faster than conventional extreme-

Table 5

Park the vehicle on level ground, apply the park-
ing brakes, and chock the tires.

Remove the axle carrier fill plug (see

Fig. 3

then remove the drain plug from the bottom of
the housing and completely drain the lubricant
while the unit is warm. Allow sufficient time for all
old lubricant to drain. On dual drive axles, it is
also necessary to remove the plug at the bottom
of the interaxle differential housing to drain the
lubricant.

Meritor Drive Axle Recommended Lubricant

Lubricant Type

Ambient Temperature

Lubricant SAE Viscosity Grade

Meritor Specification

Synthetic Gear Oil

–40°F (–40°C) and up

75W–90

0–76–N

–40°F (–40°C) and up

75W–140

0–76–M

There is no upper limit on these outside temperatures, but axle sump temperature must never exceed 250°F (121°C).

Table 5, Meritor Drive Axle Recommended Lubricant

If so equipped, replace the axle oil filter. Remove
the oil filter, using a suitable filter strap wrench.
See

Fig. 6

. Discard the filter.

NOTE: There may be about one pint (0.5 L) of
lubricant remaining in the filter. Be careful not to
spill it when removing the filter.

Using the specified drive axle lubricant, coat the
face of the gasket on a new oil filter. Install the
filter over the adapter, and tighten the filter one
full turn after the gasket contacts the base; do
not overtighten the filter.

For a new or reconditioned axle, flush the axle
with clean flushing oil, then drain it thoroughly. It
is necessary to flush the axle the first time (only)
that the axle lubricant is changed.

IMPORTANT: Axles should not be flushed with
any solvent, such as kerosene.

f350119a

05/27/93

Fig. 6, Axle Oil Filter Removal

Rear Axle

35/5

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

NOTE: Meritor recommends plugs with ele-
ments having a minimum pickup capacity of
1-1/2 pounds (0.7 kg) of low-carbon steel, in
plate or bar form. Magnets will rapidly lose ef-
fectiveness 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 plug(s), install and
tighten to 35 lbf·ft (47 N·m).

With the vehicle on a level surface, fill the axle
housings to the bottom of the fill hole, using
specified lubricant. See

Table 5

for recom-

mended axle lubricants, and

Table 6

for drive

axle lubricant capacities.

Meritor Drive Axle Lubricant Capacities

Axle Model

Capacity

pints (liters)

Single-Drive, Single Reduction

†

RS–21–160

39.5 (18.7)

RS–23–160

39.5 (18.7)

RS–23–161

37.2 (17.6)

RS–23–185

47.3 (22.4)

RS–25–160

37.2 (17.6)

Tandem-Drive, Single Reduction

RT–40–145, RT–40–145A,

RT–40–145P

Forward

30.2 (14.3)

Rear

25.8 (12.2)

RT–44–145, RT–44–145P

Forward

29.3 (13.9)

Rear

25.1 (11.9)

RT–46–160, RT–46–160P

Forward

39.1 (18.5)

Rear

34.4 (16.3)

Quantities listed are approximate. Fill axle until lubricant is level with bot-

tom of fill hole with vehicle on level ground.

†

See "Traction Equalizer Additives" in the text.

Table 6, Meritor Drive Axle Lubricant Capacities

NOTE: Some Meritor axles have a small tapped
and plugged hole near and below the housing

lubricant fill hole. This smaller hole is for a lubri-
cant temperature indicator only, and should not
be used as a fill or level hole.

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

10. Whenever the interaxle differential housing has

been drained, add an additional 2 pints (1 L) of
specified lubricant directly into the interaxle differ-
ential housing.

11. For a two-speed axle with a shift unit, change

the shift unit lubricant; see elsewhere in this
maintenance operation for the shift unit lubricant
changing procedure.

12. Remove the chocks, then drive the vehicle, un-

loaded, for 1 or 2 miles (2 or 3 km) at speeds
not to exceed 25 mph (40 km/h), to thoroughly
circulate lubricant throughout the carrier and
housing assemblies.

Two-Speed-Axle Shift Unit
Lubricant Changing

Dana Spicer and Meritor Axles

Remove the shift unit housing cover. See

Fig. 7

Drain and discard the old lubricant. Discard the
housing cover gasket.

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

f350021a

08/06/93

Housing Cover Gasket

Oil Fill Plug

Shift Unit Housing Cover

Fig. 7, Two-Speed-Axle Shift Unit

Rear Axle

35/6

Install the housing cover and a new cover gas-
ket. Tighten the housing cover capscrews 7.5 to
9.2 lbf·ft (10.2 to 12.5 N·m), then remove the oil
fill plug from the cover.

IMPORTANT: When the ambient temperature is
above 0°F (–18°C), use SAE 10 heavy-duty en-
gine oil, API service classification SD (sulfated
ash content must not exceed 1.85%). When the
ambient temperature is below 0°F (–18°C), use
one part kerosene to three parts SAE 10 heavy-
duty engine oil, API service classification SD
(sulfated 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 it with kerosene. To
prevent component damage, do not mix engine
oil and automatic transmission fluid.

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

Apply a small amount of Loctite® 242, or equiva-
lent sealant, to the threads of the fill plug. Install
the plug finger-tight on the rear axle housing.
Use a wrench and tighten it an additional 1-1/2
turns.

35–02 Axle Breather and Axle

Lubricant Level
Inspection

Detroit

™

NOTICE

Failure to keep the rear axle filled to the proper
level with the recommended lubricant can result in
rear axle damage.

Park the vehicle on a level surface, shut down
the engine, and set the parking brake. Chock the
tires.

If the vehicle has just been driven, allow a few
minutes for the lubricant to settle.

IMPORTANT: On Detroit axles, the oil change
interval for long haul vehicles can be extended
to 500,000 miles (800 000 km) for axles with
weight ratings of 34,000 to 40,000 lb (15 000 to
18 000 kg) using synthetic lubricant if a lubricant
analysis shows adequate quality. Oil must be
changed at least every four years, and more
often if the axle is exposed to high temperatures
and steep grades.

Clean the fill plug and the area surrounding the
fill plug on the side of the axle carrier. Remove
the plug. Check lubricant level when the axle is
cold, or near room temperature.

NOTE: Some Detroit axles have a small tapped
and plugged hole near and below the housing
oil fill hole. This smaller hole is for a lubricant
temperature indicator only, and should not be
used as a fill or level hole.

Check that the lubricant is level with the bottom
of the fill hole. See

Fig. 2

. If low, check for oil

leaks, and correct as needed. Add oil to the level
of the fill plug, using the lubricant recommended
in

Table 1

IMPORTANT: A lubricant level close enough to
be seen or touched is not sufficient. It must be
level with the bottom of the fill hole.

Install and tighten the fill plug 30 lbf·ft (41 N·m).

IMPORTANT: Always check the axle breather
whenever checking the lubricant level. Check
the breather more frequently under adverse op-
erating conditions.

Check the axle housing breather. Make sure that
it is open and unclogged. If the breather is
plugged or damaged, clean or replace it as
needed.

Dana Spicer Axle

NOTICE

Failure to keep the rear axle filled to the proper
level with the recommended lubricant can result in
rear axle damage.

Park the vehicle on level ground, apply the park-
ing brakes, and chock the tires.

Rear Axle

35/7

If the vehicle has just been driven, allow a few
minutes for the lubricant to settle.

Clean the oil fill plug and area surrounding it,
then remove the plug from the fill hole (see

Fig. 3

), or from the standpipe (if so equipped)

installed in the fill hole.

IMPORTANT: A lubricant level close enough to
be seen or touched is not sufficient. It must be
level with the bottom of the fill hole (see

Fig. 2

or the top of the standpipe opening.

Lubricant should be level with the bottom of the
fill hole (see

Fig. 2

), or with the top of the stand-

pipe opening. If low, check the axle for oil leaks,
and correct as needed. Add lubricant as re-
quired. See

Table 3

for recommended drive axle

lubricants.

IMPORTANT: Axle housing breathers (see

Fig. 8

) must remain clean and unclogged. Al-

ways check the axle breather whenever check-
ing lubricant level. Ensure that it is open and
unclogged. Check the breather more frequently
under adverse operating conditions. If the
breather is plugged or damaged, clean or re-
place it as needed.

Install and tighten the fill plug 40 to 60 lbf·ft (54
to 81 N·m).

For a two-speed axle with a shift unit, check the
lubricant level of the shift unit; see elsewhere in
this maintenance operation for the shift unit lubri-
cant level inspection procedure.

Remove the chocks from the tires.

Meritor Axle

NOTICE

Failure to keep the rear axle filled to the proper
level with the recommended lubricant can result in
rear axle damage.

Park the vehicle on level ground, apply the park-
ing brakes, and chock the tires.

Clean the fill plug and the area surrounding the
fill plug on the side of the axle carrier. See

Fig. 3

. Remove the plug.

NOTE: Some Meritor axles have a small tapped
and plugged hole near and below the housing

oil fill hole. This smaller hole is for a lubricant
temperature indicator only, and should not be
used as a fill or level hole.

Check that the lubricant is level with the bottom
of the fill hole. See

Fig. 2

. If low, check for oil

leaks, and correct as needed. Add the specified
lubricant. See

Table 5

for recommended drive

axle lubricants.

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

IMPORTANT: Axle housing breathers (see

Fig. 9

) must remain clean and unclogged. Al-

For a two-speed axle with a shift unit, check the
lubricant level of the shift unit; see elsewhere in
this maintenance operation for the shift unit lubri-
cant level inspection procedure.

On non-drive axles using oil-lubricated wheel
bearings, check oil level at the wheels, and add
oil if low. Use the same lubricant as specified for
the drive axle.

f350002a

06/07/94

Axle Housing Breather

Fill Plug

Temperature Indicator Plug

Fig. 8, Dana Spicer Axle Housing Breather

Rear Axle

35/8

Content .. 21 22 23 24 ..