Fleet Maintenance - 14

Humphrey adds that while there is no official
rule, the oil industry typically agrees that a blend
needs to include at least 30 percent synthetic oil
for it to be called a synthetic blend.
Performance and technology:
CK-4 and FA-4
The third way engine oils can be categorized is
by performance - how well the oil holds up to
extreme conditions. Modern diesel engines are
designed to be more efficient and longer lasting
than previous generations, so they have tighter
clearances and closer tolerances, and tend to run
hotter. It's more important than ever for engine
oils to be resistant to oxidation, shear, and aeration. CK-4 and FA-4 oils, the latest evolution in
engine oil technology, were designed specifically
to withstand these demanding conditions.
"The biggest change in the past few years has
been the splitting of the diesel engine oil category into two separate categories," says Kevin
Ferrick, director of API product programs.
"API CK-4 oils succeeded CJ-4 engine oils and
are backward compatible diesel [engine] oils.
Backward compatible means CK-4 may be used
where CJ-4 ... CI-4, CH-4, and earlier service categories are recommended. API FA-4, on the other
hand, is new and intended for engines beginning
with the 2017 model year."
Ferrick says that while the two oils provide
similar protection, FA-4s have lower viscosity
grades to meet the needs of next-generation diesel
engines and help improve fuel economy. He notes
that CK-4 and FA-4 oils both provide improved
oxidation resistance, shear stability, and aeration
control over CJ-4.
ÜÜOxidation. Oil oxidation is a chemical reaction
that degrades the quality of the oil. "Oil oxidation is one of the main reasons for oil breakdown, and it occurs more readily under higher
engine operating temperatures," Ferrick says.
"With many newer engines running hotter, CK-4
and FA-4 standards deliver improved oxidation
stability versus CJ-4 oils."
ÜÜShear. As oil passes through the engine and
is worked by different components, it goes
through a process known as shear, in which the
molecules are split apart, lowering the viscosity
of the oil. This can have a negative impact on
how well the oil protects the engine, leading
to increased wear and potential damage. CK-4
and FA-4 oils have improved shear stability
compared to CJ-4 oils, Ferrick says.
ÜÜAeration. "As the oil is being whipped through
the engine, it absorbs air," says Paul Cigala,
commercial vehicle lubricant application engineer at ExxonMobil, an international oil and
gas company. "When those air bubbles are in
tight places, they pop and ... can make marks on
metal surfaces and eventually can cause internal damage inside of an engine." CK-4 and FA-4
oils were designed to release these air bubbles
to avoid potential damage to the engine.
CK-4 and FA-4 oils are a clear improvement
over previous generations' oils, but it is imperative for fleets to use the proper oils in each
vehicle. While CK-4s are backward compatible,
FA-4s should only be used if the manufacturer
specifically recommends it for the engine in
question. When making the switch from previ-

14 Fleet Maintenance | May 2019

Benefits of oil
drain valves
When collecting samples for used oil analysis, it is important to know where on the
engine the oil is coming from. Paul Cigala,
commercial vehicle lubricant application
engineer at ExxonMobil, recommends pulling live samples out of the engine block.
"Live samples out of the engine block with a
push-button valve that's either in the side of
an oil gallery or somewhere where there's live
oil flowing gives us the best results," he says.
There are many companies that make oil drain
valves, both for pulling samples and for draining the oil during an oil change. Many oil drain
valves replace the standard drain plug, while
others install in a more convenient location.
These products make the oil drain process
easier and less messy by allowing oil to flow
with the twist of a lever, rather than having to
unscrew a drain plug while oil flows around it.
"You can get a sample valve installed from
the factory, and it makes it so much easier to
take a sample at any time because it's always
installed," Cigala says. "It's a pretty nice setup.
I have a lot of fleets that outfit their whole
fleet with it when they order new trucks, and
then they retrofit older trucks with it, so it's
just a one-stop process for their techs."

ous generation oils to the new standards, it is
important for storage and dispensing equipment to be properly labeled and technicians to
be properly notified and trained. (See sidebar,
page 12: Best practices when switching to CK-4 and
FA-4 heavy duty engine oils.)

Used oil analysis

Knowing which oil to use is one matter, but knowing that the oil a fleet is using is doing its job to
protect the engine is another entirely. A good way
to keep this in check is through used oil analysis,
a process in which the fleet takes a sample of used

»»When conducting used oil analysis, a technician
must collect a sample of used engine oil to be
sent in for testing. ExxonMobil advises samples
should not be taken from the drain pan.
Photo courtesy of ExxonMobil Lubricants

engine oil from the vehicle and sends it to a laboratory to be analyzed.
Collecting the sample
During an oil drain is a good time for a technician
to collect a sample of used engine oil to be sent in
for testing. ExxonMobil's Cigala cautions, however,
not to take the sample from the drain pan.


Fleet Maintenance

Table of Contents for the Digital Edition of Fleet Maintenance

Uptime - Are You Communicating with Employees Effectively?
Trends in Heavy Duty Diesel Engine Oils
Vehicles - Keys to Consistent Liftgate Performance
In the Bay - How Standardized Vehicle Communication Protocols Impact Diagnostics and Vehicle Operation
Shop Operations - Considerations for Mobile Device Usage in the Shop
Training - Where are all the Students Going?
Management - Why the Recent Airline Accidents Should be Concerning
Fleet Parts & Components
Tools & Equipment
Guest Editorial - How Much Do You Spend on DPF Maintenance?
Fleet Maintenance - 1
Fleet Maintenance - 2
Fleet Maintenance - 3
Fleet Maintenance - 4
Fleet Maintenance - 5
Fleet Maintenance - 6
Fleet Maintenance - 7
Fleet Maintenance - Uptime - Are You Communicating with Employees Effectively?
Fleet Maintenance - 9
Fleet Maintenance - Trends in Heavy Duty Diesel Engine Oils
Fleet Maintenance - 11
Fleet Maintenance - 12
Fleet Maintenance - 13
Fleet Maintenance - 14
Fleet Maintenance - 15
Fleet Maintenance - 16
Fleet Maintenance - 17
Fleet Maintenance - Vehicles - Keys to Consistent Liftgate Performance
Fleet Maintenance - 19
Fleet Maintenance - 20
Fleet Maintenance - 21
Fleet Maintenance - In the Bay - How Standardized Vehicle Communication Protocols Impact Diagnostics and Vehicle Operation
Fleet Maintenance - 23
Fleet Maintenance - 24
Fleet Maintenance - 25
Fleet Maintenance - 26
Fleet Maintenance - 27
Fleet Maintenance - Shop Operations - Considerations for Mobile Device Usage in the Shop
Fleet Maintenance - 29
Fleet Maintenance - 30
Fleet Maintenance - 31
Fleet Maintenance - 32
Fleet Maintenance - 33
Fleet Maintenance - Training - Where are all the Students Going?
Fleet Maintenance - 35
Fleet Maintenance - Management - Why the Recent Airline Accidents Should be Concerning
Fleet Maintenance - Fleet Parts & Components
Fleet Maintenance - 38
Fleet Maintenance - 39
Fleet Maintenance - 40
Fleet Maintenance - Tools & Equipment
Fleet Maintenance - 42
Fleet Maintenance - 43
Fleet Maintenance - 44
Fleet Maintenance - Classifieds
Fleet Maintenance - Guest Editorial - How Much Do You Spend on DPF Maintenance?
Fleet Maintenance - 47
Fleet Maintenance - 48