- Stoneway Concrete chose the Kenworth T880 truck with a PACCAR MX-11 engine to replace its older fleet, after testing showed its advantages in payload capacity, stability, and profitability. - The T880 with MX-11 can carry up to 12 yards of concrete per load, generating $315 more daily revenue compared to older 10.5 yard trucks. This leads to an estimated $98,000 more annual revenue per truck. - The lighter MX-11 engine, set-back front axle, and additional pusher axle improve the truck's weight distribution and stability while maintaining power.

1. Kenworth Truck Company News Release
Stoneway Concrete Realizes Greater Payload, Enhanced
Stability with Kenworth T880, PACCAR MX-11 Engine
RENTON, Wash. – When Ralph Lo Priore
looks at which new specification choices would
likely work best for his company’s trucks, he
prefers to deal in cold hard facts, not egos or
emotions.
Ralph Lo Priore is director of fleet assets and processes for
Stoneway Concrete and its parent company, Gary Merlino
Construction Co.
“Too often people make purchasing decisions
on what’s always been done before,” said Lo Priore,
director of fleet assets and processes for Stoneway
Concrete and its parent company, Gary Merlino
Construction Co. “Instead, I like to look at what’s
going to deliver the best return on investment in
terms of reliability, durability, serviceability,
longevity and a lower cost of operation.”
Stoneway and Merlino operate a combined
fleet of 150 trucks, including 85 transit mixers and
60 dump trucks from three locations – the
company’s maintenance shop in Renton,
Washington, a yard in South Seattle and another
yard next to Ashgrove Cement in Seattle.
When it came time to choose a new engine
platform for Stoneway’s mixers, Lo Priore
examined the data and chose the new PACCAR
MX-11 engine platform with two Kenworth T880
mixer chassis for Stoneway Concrete. After those
two T880s with the MX-11 proved their worth in
operation, Lo Priore ordered nine more new
similarly spec’d T880 mixers.
PACCAR MX-11 Engine
(continued)

2. (continued)
“I look at, for example, the company’s
maintenance data, which helps me identify issues
caused by bad spec’ing decisions, like equipping a
truck with the wrong suspension,” Lo Priore said.
Of course payload is always a major
consideration, Lo Priore added. “Our customers are
always wanting more yardage with fewer trucks on
the job. That’s why when I looked at how many
times the company sent out one more mixer to a job
site with short loads of concrete to finish up the job,
I knew Stoneway Concrete needed trucks with more
payload capacity.
“But trying to get that additional payload by
going with the same 13-liter engine and looking for
weight savings in other places, or going bigger with
a 15-liter engine in applications other than the
mixers, were just not the right options,” he said.
Lo Priore also credits the new model’s success
to a decision to go with a set-back front axle and a
total of seven axles, including a conventional
“boost-a-load” axle, allowing for an 80,000-pound
GVW, which is allowed under Washington state’s
bridge formula. Lo Priore said he saw the more
typical 76,000-pound GVW design with an 11-yard
mixer as being “obsolete.”
While many questioned those choices, Lo
Priore said he felt confident they were the right
ones. That’s because with the PACCAR MX-11, the
tractors and mixers realize a better horsepower-to-
weight ratio and gain payload capacity. And with
the combination of the MX-11 and set-back front
axle, the T880 mixers can carry 4,000 additional
pounds of payload by redistributing the weight to
the pusher axle when needed.
The additional payload capacity means the
mixers can carry up to 12 yards of concrete per load
instead of the usual 10-1/2 to 11 yards the typical
76,000-pound GVW Stoneway mixer equipped with
a 13-liter engine would carry. With a 12-yard
capacity, the T880 mixer with PACCAR MX-11
engine can generate an average of $315 more in
daily revenue than a 10 1/2-yard mixer. Stoneway
Concrete’s mixers typically run six days a week
year-round, and as a result the T880 mixer can earn
about $98,000 more in annual revenue, according to
Lo Priore.
(continued)

3. (continued)
The lighter engine, set-back front axle and
addition of the pusher axle all changed the T880’s
center of gravity, allowing McNeilus to install a
wider drum, Lo Priore said. By pushing the front
axle back, the drum also sits lower on the frame,
which results in increased stability and reduced
drum bounce, in on- or off-road conditions.
“By choosing the PACCAR MX-11, we have a
400-pound lighter engine compared to a 13-liter
engine, but with the same 430 horsepower,” Lo
Priore added. “The MX-11 engine, with its compact
graphite iron head and block, is much lighter and
more durable than an engine made of gray cast iron.
With the Allison 7-speed automatic transmission,
it’s a perfect combination.
“Allison’s dynamic shift sensing allows the
transmission to automatically choose gears based on
the vehicle’s weight and the road grade. So, drivers
get a state-of-the-art truck that doesn’t leave them
tired with aching knees and shoulders from all of
the shifting they have to do in city traffic,” he said.
“And the Kenworth T880 provides us the right
chassis because of its design, which makes for a
more comfortable work environment and offers a
field of view drivers simply can’t get with the other
available truck models.”
Dan Leenhouts, who was assigned that first
Kenworth T880 mixer with the PACCAR MX-11
engine in 2015, was so impressed by it, he chose to
forgo his retirement in 2016 and continue working
another two years for Stoneway.
Dan Leenhouts, Stoneway Concrete driver, is shown with a
Kenworth T880 mixer equipped with a PACCAR MX-11
engine.
“The Kenworth T880 offers such a phenomenal
ride,” he said. “When I first drove it, I just could not
believe how quiet it is in the cab. Because the MX-
11 provides good power and smooth acceleration, I
find the T880 is able to keep up with the other
trucks with larger engines, even lugging under load
on hills.
“I’m also very, very pleased with the visibility
from the cab,” Leenhouts said. “The mirrors are so
perfectly positioned giving me the ability to
maneuver well in heavy traffic. With its sloped
hood, driving the T880 is almost like driving a
cabover.”
Lo Priore said it wasn’t easy to get a concrete
mixer equipped with a set-back front axle, an 11-
liter engine, and seven axles including a pusher
axle, built. After he shared data from Stoneway’s
conditions-based maintenance program, “Kenworth
was the only OEM willing to try,” he added. Lo
Priore credits Rick Barry, territory sales director at
Kenworth Northwest, and Kenworth technical
engineers in making the spec happen.
(continued)

4. (continued)
From left, are Dan Leenhouts and Ralph Lo Priore of
Stoneway Concrete
“Now that we’ve proven what this new spec
can achieve, I take pride that there’s a lot of other
companies looking very hard at whether this new
specification can work for them as well as it has for
us,” Lo Priore said.
Kenworth is the driver’s truck. See what
drivers are saying at www.kenworth.com/drivers.
Kenworth Truck Company is the manufacturer
of The World’s Best® heavy and medium duty
trucks. Kenworth's Internet home page is at
www.kenworth.com. Kenworth is a PACCAR
company.