In addition, Kolany notes the washer should
spin freely on the nut. If it doesn’t, he advises to
replace the lug nut stud.
Jamie Untersinger, Business Development
Manager, Vehicle Inspection Systems, recommends
the “R.I.S.T.” checklist for the removal and
replacement of wheels, to help reduce the chance
of a wheel-off situation:
ÂÂRemove the lug nuts and wheels.
ÂÂInspect the studs for stretching, nuts for
stripped threads, and wheels damage and
ÂÂSnug the lugs.
ÂÂTorque the wheel bolts using the desired torque
pattern and correct lb-ft.
Vehicle Inspection Systems promotes brake and
undercarriage inspection as well as wheel and rim
safety products for the commercial vehicle industry.
What to review during inspections
Whether it’s pre-and post-trip inspections by drivers,
or assessing the wheel-end system as part of
regular preventative maintenance, visual checks
can provide warning signs to issues. Fleets should
look for any broken or damaged components, and
for any leakage around seals and hub cap gaskets.
28 Fleet Maintenance | June 2018
Depending on the type of lubrication method,
Stemco’s Purvis recommends inspecting the hub
for the following:
ÂÂFor oil bath wheel-ends: Visually inspect, using
the hub cap window, to verify proper oil fill level
and lubricant integrity.
ÂÂFor semi-fluid grease wheel-ends: Look for any
significant variation in hub temperatures upon
in-service inspections, accounting for seasonal
For pre-and post-trip inspections, “the lubricant
levels are easy to check,” Timken’s Domin
confirms. “Additionally, look for wetness on the
back of the wheel which could indicate a seal leak.”
“When performing a wheel-end inspection, the
technician should check the wheel bearing seal for
signs of excessive leakage, the hub assembly for
excessive endplay and the hubcap or axle flange
for signs of lubricant indicating a leaking gasket
or possible damage to the hubcap,” Domin adds.
SKF’s Kolany says it is critical to have drivers
properly trained to inspect wheel-ends. In addition
to educating drivers on proper techniques
to confirm possible lubricant leakage, they can
visually inspect for slipping or missing lug nuts
and other aspects of the unit.
“If the lug nuts are loose or backing off you will
notice rusty discoloration or lines as if they’re
slung from the wheel bolt area,” Vehicle Inspection
Systems’ Untersinger adds. “This is a good indication
torque should be re-checked immediately.”
Drivers should also physically touch the wheelend
assembly during a post-trip inspection to
confirm heat generated from the unit.
“Warm to (the) touch is normal but when too hot
to touch, there is a problem,” Kolany says.
Regarding operating temperature, it is recommended
the wheel-end temperature record at
no higher than ambient temperature-plus-150
degrees F. In other words, if it is 50 degrees outside,
the temperature should not exceed 200 degrees F.
“Heavy braking or a dragging brake can also
effect wheel-end operating temperature,” ConMet’s
High temperatures can be indicative of a more
widespread problem with other areas of the vehicle
like the braking system.
“Overheated brakes can cause excessive heat
to the wheel hub that can damage the seal and
cause the seal to leak lubricant onto the brake
shoes,” Domin says. “In such instances, the brakes
will be less effective and cause increased stopping
distances, which will, in turn, apply more heat
to the wheel-end and cause more seal damage.”
Pre- and post-trip checklist for wheel-ends
Roger Maye, National Service Manager for
Consolidated Medco, Inc. (ConMet), provides
the following tips when reviewing wheel-end
systems for pre-trip or post-trip inspection:
• Check the oil level and condition on steer
and trailer hubs lubricated with oil.
• On oil lubricated wheel-ends, use
a magnet to look for metallic particles
that may be in the lubricant.
• Look for loose, missing or broken fasteners
on the hub cap, drive axle and wheel bolts.
• Check for leaking hub caps.
• Check for cracked or broken wheels.
• Look for dark or rusty stains coming
from the wheel bolts that may
be a sign of loose fasteners.
• Visually inspect the inside of the
wheel and brake assembly for
signs of leaking wheel seals.
• Visually inspect the brake-related
components on the wheel-end at this time.
Specifics for lubrication of wheel-ends:
• On steer axles, monitor the lubricant
condition and fill level. Look for signs
of contamination and use a magnet
to check for metallic particles.
• On drive axles, remove the fill plug in the barrel
of the hub, if so equipped, and check the
lubricant condition. Use a magnet to inspect
the lubricant for metallic particles. Also be
sure to check the condition and fill volume
of the lubricant in the drive axle housing.
• On trailer hubs lubricated with oil, check
the lubricant condition and fill level.
• On trailer hubs lubricated with semi-fluid
grease, remove the hub cap and check
the quantity and condition of the lubricant.
Be sure the ends of the bearing
rollers are covered with lubricant.
• On all wheel-ends, when the axle is lifted
off of the ground for service or inspection,
use a pry bar to lift the wheel and check
for ‘chucking’ or loose bearings. If loose
bearings are found, use a dial indicator
to verify the wheel bearing endplay.
If there are issues with any of the inspection
checks listed above it is critical to correct
any problems found during the inspection
before placing the vehicle back into service.
»»Vehicle Inspection Systems offers
the VIS Squirrel, which holds lug nuts
in place via the wheel bolt.
Photo courtesy of Vehicle Inspection Systems
Systems offers the
VIS Squirrel, which
holds lug nuts in place
via the wheel bolt.
“It is a high-strength
polymer that has
corrugated ridges inside
and out so it stays
in constant contact
with all lugs holding
nuts in their place,”
Photo courtesy of Vehicle