freightliner BUSINESS CLASS M2 100, Maintenance Manual

Page: 101 / 198

8. Read the toe-in from the scale, and compare it to
the toe-in specification in
Group 33 of the ve-
hicle Workshop Manual. If corrections are
needed, refer to
Group 33 of the vehicle Work-
shop Manual for instructions on adjusting the
toe-in.
33–07 Steer Axle Hub Cap Vent
Plug Inspection
General Information
As a function of their design, hubcap vent plugs will
on occasion exhibit signs of hub oil on their exterior
surface. Depending on environmental conditions
and/or age of the plug, the amount of oil present can
vary. This is a normal result of the venting process
due to pressure increase within the hub cavity. For
an example of normal vent plug appearance, see
Fig. 13 .
A vent plug can wear or be damaged and cause ex-
cessive leakage, or allow water to enter the hub and
contaminate the oil. For examples of a leaking vent
plug, see Fig. 14 and Fig. 15 . Evidence of a leaking
vent plug may appear as;
•
Oil splatter around the wheel
•
Gooey/gummy oil around the vent plug purge
point
•
Hub/plug area is dirty, and water contaminated
oil in the hub.
•
Hub/plug area is clean, but there is water con-
taminated oil in the hub. (pressure washing is
the most likely cause)
Inspection
NOTICE
Only remove vent plugs by hand. They can be
damaged if a tool is used. Wipe the hub/plug area
clean before checking the oil. Do not use a pres-
sure washer to clean the hub/plug area. The plug
has a vent and this can contaminate the oil with
water.
1. Park the vehicle on a level surface, shut down
the engine and set the parking brakes. Chock
the tires.
2. Inspect the axle hub cap and vent plug for evi-
dence of excessive leakage.
3. Wipe the hub cap and vent plug clean with a rag.
f400100a 10/05/2016
Fig. 12, Setting Trammel Bar Pointers
f3302 9 8 0 9 /01/2016
Fig. 13, Normal Oil Venting
Front Axle
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