april2023 - 15

" If a fleet has developed
its own maintenance
checklist based on a
shorter lifecycle, it is
important to update
the inspection form
to include the OEM's
recommendations out to
their extended lifecycle. "
Anthony Balkonis, VP of services
and warranty at Navistar
system. That becomes a ticking time bomb in a
vehicle with more than half a million miles on
it. " This is what can lead to things like bearing
failure, " Nynas pointed out. " It's a good idea to
simply replace the O-rings and seals in a lubrication
system at this point. "
Air dryers should also be thoroughly examined,
and we're not just talking about the desiccant
cartridge. The entire module should be inspected.
An air dryer also has a valve and most have heaters.
" These things are typically about shot by this
point, " Nynas said. " Simply getting them replaced
is probably a good idea. "
Turbocharger issues also tend to plague heavier-duty
trucks-especially the ones that have quite
a bit of time under their belts.
" Oil breaks down, " said Josh Steinmetz, brand
batch of service items at half a million miles.
" Most OEMs have maintenance guidelines well
beyond when the first owner normally keeps the
truck, " Balkonis said. " If a fleet has developed its
own maintenance checklist based on a shorter
lifecycle, it is important to update the inspection
form to include the OEM's recommendations out to
their extended lifecycle. Components they would
not have needed to inspect when trading a truck at
their prior lifecycle may now need to be serviced
or replaced. "
For instance, Balkonis said it's important to
look at things like suspension bushings, A-cams,
harnesses, and cable routing. S-cams and tubes
are another overlooked area. " S-cams are rarely
removed unless they are frozen. But as a vehicle
ages, bushings can wear out. Catching that quickly
helps keep the unit on the road and prevents a
major brake assembly overhaul, " Balkonis said.
Braking system inspections should also include
a couple of additional steps.
" I'd be looking at brake hoses, " Celentano said.
" The plastic ones tend to dry out and sometimes
split at the crimp. "
» It's important to make sure technicians
have the training they need to perform
the services necessary after 500,000
miles. Diesel Laptops provides both online
and hands-on classroom training.
Diesel Laptops
O-rings are also at the top of the list, according
to Nynas.
" Over time, after exposure to detergents in
the oil, O-rings start to get hard and brittle and
shrink, " Nynas said. " You might start experiencing
some leakage. But the bigger issues are
inside the engine-things like oil pickup tubes
and suction manifolds. "
As Nynas explained, degraded O-rings start
to allow air contamination in the lubrication
manager at Lubrication Specialties, a provider of
oil, lubricants, and additives whose brand names
include Hot Shot's Secret. " At the end of a long day,
that oil is really hot. The bearings on a turbo are
extremely hot. If you don't let that oil cool down
and cycle through, it actually burns right onto the
turbo bearings. That can cause a lot of issues over
time. You might even see bearing failure. "
In a case like this, a technician may need to
rely on driver input because visual indicators
April 2023 | FleetMaintenance.com
15
http://www.FleetMaintenance.com
april2023

Table of Contents for the Digital Edition of april2023
