march2022 - 18

a day, and to fight a pull in the steering or deal
with vibration is understandably frustrating and
fatiguing. I have seen drivers leave because of a
drivability issue. "
Lamoreaux also worked at Blaine Brothers'
TruckAline business, which as the name suggests,
handles alignments and other axle and suspension
service items. The services are also used in-house
on Blaine Brothers' fleet of light- and medium-duty
trucks, as well as tow trucks.
They use a mix of preventive maintenance
scheduling and driver feedback.
" Our vehicles are on our PM program/schedule
to monitor for upcoming or unexpected issues, and
our heavy tow trucks are aligned whenever the
steer axle tires are replaced or if there is a concern
reported from our drivers on their DVIR, " noted
Blaine Brothers CEO Dean Dally.
Dally also advised to seek out regular alignments
at a reputable alignment shop.
" A good alignment shop should identify potential
issues that may arise based on current tire
wear patterns and with a good thorough inspection
before doing the alignment, " he said.
This goes a long way in maximizing steer tire life.
" If the truck was aligned each time the steer
tires were replaced, at a minimum, a lot of drivability
issues could be avoided, " Dally asserted.
Lamoreaux added that shops should not align
a truck with worn steering or suspension parts.
" Kingpins, steering linkages, and suspension
pivot points are always checked, and anything
with play is shown to the customer to let them
know our recommendation and let them decide
whether to proceed, " he said. " Excessive play will
not be aligned, and customers will be advised on
repairs needed. "
When alignments are done, Lamoreaux said an
absolute must is making sure one person is designated
to pre-drive the truck and also test drive
that truck when it comes off the rack. He suggested
some high-volume shops just go off what the
computer says in terms of the positive/negative
value of the laser alignment. Technicians should
test-drive to confirm proper alignement.
This help shops retain customers, too, as a driver
who feels off-balance after a fresh alignment
would likely not return.
Suspension spec'ing considerations
" If you don't have the right suspension, it's going to bounce you out of the
chair, and you'll hit your head on the ceiling, " offered Tim Wrinkle, Mack
Trucks product manager, construction, talking about drivers traversing an
uneven work site.
Wrinkle explained a driver would likely have to creep along to prevent this,
extending the time it takes to move across a job site. That lowers productivity
and increases driver frustration. The fix for a smoother ride is usually
opting for an air ride suspension, which cushions the kinetic energy from
the ground with air bags. Air is provided directly by the compressor, or
via a secondary air tank on the trailer. The extra complexity of this system
increases cost and maintenance considerations.
Wrinkle said another trade-off is less traction for vocational trucks with air
ride, which for some extreme duty cycles is more necessary than comfort.
" It's all for naught if you get stuck, and you lose a couple of hours of time
because a bulldozer has to come and free your dump truck, " Wrinkle said.
" Air ride is
unsurpassed
when it comes
to providing
the comfort
drivers need to
avoid fatigue
issues. "
Bryan Redeker,
product manager,
powered vehicle
systems, SAF-Holland
He said the Mack mRIDE provides a balanced
alternative. The system uses parabolic
springs for strength and flexibility. The
tires articulate 15 " in either direction, allowing
them to always contact the ground.
TRAILER SPEC'ING
Deciding on air or spring ride really depends
on the duty cycle and if the suspension will
go on a dry van or specialty trailer.
Some fleets, such as Schneider, prefer
mechanical springs for lower upfront and
maintenance costs. After pitting a leading
spring-ride suspension against four air ride
counterparts, Schneider concluded: " Air ride
does not guarantee greater ride quality than
spring. It's a myth. Knowing this, Schneider
can't justify spending more on air ride and
recommends shippers don't either. "
A key factor was air bags' vulnerability to
damage and thus potential for unplanned
downtime.
But that study was done many years ago and there's plenty of nuance to
finding the right type of suspension.
For example, Hendrickson offers more than two dozen different trailer suspensions
and more for the tractor. To help spec the proper trailer suspension,
the company offers the comprehensive L707 Application Guide.
But a chart won't tell you everything. Don Hester, senior program manager
of sliders and suspensions at Hendrickson, encourages customers to ask the
right questions and not stop until they receive answers they are comfortable
18 Fleet Maintenance | March 2022
» The Mack mRIDE suspension allows 15 " of articulation
to keep the tires grounded and ride more smooth.
Photo: Mack Trucks
with. These include asking about bridge laws in operating regions, the type
of axles that will best serve the application (tandem or tri-axle, for example),
and whether or not to install a lift axle.
The type of trailer and duty cycle will help point a fleet in the right direction.
According to Bill Hicks, product manager, trailer suspension and axle systems,
at SAF-Holland, " On-highway dry freight vans have seen a shift toward
the mechanical spring ride tandem sliders, which are now the majority rather
than air ride systems.
" For specialty trailers like tanks, flatbeds, bulk, etc., the air ride is the system
of choice, which can be traced to the overall value of the trailer and the
expected longer service life, " he continued.
Hicks' colleague at SAF, Bryan Redeker, product manager, powered vehicle
systems, also lauded air ride for the driver benefits.
" Air ride is unsurpassed when it comes to providing the comfort drivers
need to avoid fatigue issues, " Redeker said. " High-performance air ride suspensions
not only enhance the ride comfort, but also exhibit superior roll
stability, especially when carrying high center of gravity loads over uneven
terrain, and while cornering. "
That doesn't mean spring ride should be bounced from consideration.
These mechanical suspensions can also last the life of the trailer; they are
" also typically less expensive and lighter than air ride suspensions, " noted
Dan Cordier, VP of sales at Hutchens Industries. " They are easy to maintain
and have a lower total cost of ownership, reducing the fleets' downtime and
maintenance expenses. "
Cordier concurred that applications such as car haulers, dry bulk tanks,
and wide axle base flatbed trailers would be better off with air ride.
With all these differing opinions, a sound strategy would be to involve both
the drivers and maintenance departments and find a compromise everyone
can live with.
march2022

Table of Contents for the Digital Edition of march2022
