KIC Catalog

Recommendations for Wheel End Lubrication

Hub Fill Procedures: Oil

Install the wheel seals as documented in RP 622. Ap-

ply lubricant to the bearing journals and bearing cones.

Use the same lubricant that will be used to lubricate the

system. This will help inhibit fretting corrosion and make

assembly easier. Use lifting equipment to align the hub

assembly with the spindle taking care not to damage the

seal and spindle threads. While the hub is supported/

suspended, fill the hub cavity with clean oil and push the

hub into position, or push the hub into position and then

fill the hub cavity.

Install the outer bearing, and adjusting nut systems. Ad-

just wheel bearings using TMC RP 618 or OEM Mainte-

nance Manual. Verify end play (0.001” to 0.005”) with a

dial indicator.

Hubcap Considerations: Oil

Select the proper vented, bolt-on or threaded hubcap for

the application and follow hubcap suppliers’ instructions

for proper attachment to the wheel hub. Fill wheel end

assembly through the fill port with the same oil. Allow

time for the oil to seep through the outer bearing and fill

the hub cavity. Continue to add oil until the oil reaches

the oil fill line as indicated on the hubcap. (See

Figure

NOTE

: For hubcaps with side fill plugs, do not allow the

oil to go past the centerline or vent hole.

! CAUTION

: Overfilling or under filling a wheel hub

with lubricant may result in premature component fail-

ure.

Install center fill or side fill plug. Torque side fill plug to

hubcap manufacturer’s specifications. Clean-up any

over spills that would give the appearance of a leaking

hubcap.

B. Non-Driven Grease-Lubricated Wheel Ends

NOTE:

Semi-fluid greases are NLGI 000 and 00. NLGI 0

is a soft grease. All three grades listed above are treated

as semi-fluid greases in this RP. Hard greases are de-

fined as NLGI 1, 2, and 3 consistencies in this RP.

Inspection and Preparation

Clean and inspect the wheel end components includ-

ing all bearings, hubcaps, hub and bearing cups, axle

spindle, and fasteners, removing all contaminants and

lubricant residue. Replace seal, hubcap gasket, and all

questionable parts. For detailed procedures, refer to

TMC RP 622.

NOTE

: If retrofitting an oil or grease system with a semi-

fluid grease, be sure to note the need for special clean-

ing instructions, fill procedures and equipment (i.e.,

vented hubcap).

Component Lubrication

Pack the inner and outer wheel bearing cones full with

grease. Work the grease into the bearing in the direction

of the arrow shown in

Figure 4

by machine or hand such

that the grease goes under the bearing cage toward the

cone rib and roller ends.

For corrosion prevention, place a light film of grease on

all metal components, including the hubcap. Wipe off

the excess grease. Install the wheel seals as described

in TMC RP 622.

! CAUTION

:Failure to lubricate bearing correctly

and maintain proper lubrication may result in bearing

damage. For detailed procedures, refer to TMC RP

618 and RP 622.

! WARNING

: If grease packing is done by hand,

appropriate protection — such as gloves and clothing

— should be worn to minimize skin contact with the

grease.