By Bryce Baird - Isuzu

Isuzu fills a gap
B y B r y c e B a i r d
It used to be that a Japanese truck was
pretty much bought on price, and the four
Japanese, heavy truck manufacturers active
in this part of the world were effectively
competing amongst themselves in their price
bracket.
Back then, Japanese trucks were priced so
well that buyers mostly accepted their stouter
tares, lower torque figures and their soft re-sale
values compared with those of their American
and European competitors. The Japanese trucks
proved good value, irrespective of brand, and
usually impressed with a durable product that
drivers enjoyed.
However, the world has shrunk since those
innocent days of every truck knowing its place.
Truck manufacturers have had to form alliances,
take over or be taken over to survive, and Japan
has not been immune from the winds of change.
In fact, it has proved vulnerable, as it has come
under attack from its powerhouse neighbours,
China and Korea, with India’s truck manufacturing
industry also gaining momentum.
Fuso has found sanctuary under the Daimler
Group umbrella; UD Trucks (Nissan) nestles
under Volvo’s skirts, and Hino shouldn’t have
too much to worry about, given that it is the
trucking arm of Toyota, one of the world’s biggest
corporations.
Isuzu was poised to be an even more stellar
performer. Its alliance with General Motors
was the talk of the town in the nineties and
it seemed on the brink of great things as the
North American market unfolded before it. By
1999, General Motors had a 49 percent stake in
Isuzu and effective control of the company. The
future looked glorious, with numerous vehicle
exchange agreements with other manufacturers,
primarily Honda and Subaru. However, in less
than 10 years, Isuzu had pulled out from the
North American market almost completely and
had bought back much of the shareholding once
held by GM.
General Motors’ fortunes have fluctuated
wildly since, but it’s not alone in that. Despite
hitting the reef in America, around the rest of
the world it has gone from strength to strength,
including New Zealand where it has been the
best-selling truck brand for the tenth year in a
row. Here it holds a dominant 22.8 percent of
the market and the heavy Giga range and its
Clockwise from left: Isuzu is renowned for the quality of
its diesel engines, the big the 16-litre EGR unit looks more
complicated than usual with the extra plumbing; it’s a
busy looking chassis; no matter which way you look at the
engine, the plumbing dominates; airbag suspension and an
electric retarder make for a good ride, and great braking
18 NZ Trucking September 2010 September 2010 NZ Trucking 19

predecessors are widely used in all categories of
cartage.
Isuzu’s legacy is still strong in America where
the renowned Duramax engine powers hundreds
of thousands of Chevy and GMC trucks.
Worldwide Isuzu’s small diesels can be found
in construction gear, industrial and nearly every
other application, often re-branded. Isuzu had
produced more than 21 million diesel engines
by 2009.
Despite a nearly 50 percent drop in truck sales
in New Zealand, Isuzu has held its podium placing
but it is well aware that the bigger trucks
coming out of Japan have to work much harder
to compete on the market, as the dollar gap
between the manufacturing blocks isn’t the gulf
it used to be.
Effectively, Isuzu and its Japanese compatriots
have seen their financial advantage shrink and
have needed to up the ante in the tougher climate.
Even before the world economic crisis, Isuzu
New Zealand had been refining its range, and
after more than two years of trying to plug a
hole in their line-up, they’ve presented a brandspanking
new offering.
Colin Muir, sales and marketing manager for
Isuzu New Zealand, says Isuzu believes it will
be attractive to the skeletal and container crowd
and be cheaper than the EXY530.
Isuzu has had a glaring hole in their 6x4 tractor
line-up, as the EXY530 is their smallest – and
only – air-bagged tractor in this market. There
have been other stop-gap alternatives based
around the six-rod suspension EXZ/CYZ400
rigid spec, being converted to air-suspension,
but they’ve not had a dedicated air-suspended
six-wheeler tractor of 400 horsepower on offer
– until now.
Kelly Keogh, the heavy vehicle technical and
product co-ordinator for Isuzu New Zealand,
says that in New Zealand the roles are blurred
between the models, due mainly to our small
market limiting options off the production line.
With the EXY400, Isuzu have a Euro 4, air-suspended
tractor that is priced considerably under
the EXY530; this gives them a tractor aimed at
the sidelifter and general cartage market.
Effectively it’s a new model for this country
and has refined the range for Isuzu. It’s also the
facelift template for Isuzu’s future trucks, with a
new exterior makeover. This is just the start of a
list of changes, and this tractor has morphed into
its bigger brother in nearly every respect, except
for the price – Isuzu New Zealand has worked
hard to make this truck financially accessible,
without turning it into a poverty-pack model.
The biggest news is that this truck now shares
the same powerplant as its big brother, with
Isuzu going back to a big engine to help slide
past Euro 4.
A whopping 15,681cc’s sit under the floorboards,
and that 16-litre 6WG1-TCR engine
may seem like a step back to the days when Jap
trucks often sported plenty of cubes, but modest
outputs. We had a sense of the familiar when
we looked at the spec sheet, and found that
those 16-litres are indeed light in the numbers
compared to other 16-litre units out there, but
there’s a good reason for that.
Four-hundred horsepower and 1300lb/ft of
torque may not take your breath away, but by
using a big engine and bolting on new technology
such as common rail injection, a variable
geometry turbo and a diesel oxidation catalyst
exhaust system, they’ve produced a large engine
that doesn’t need to work too hard. That translates
to lower cylinder temperatures and an easier
pathway to Euro 4 and eventually Euro 5.
The weight penalty isn’t bad either, at only 50
kilos over the previous 14-litre engine – achieved
by a modular construction that allowed a lot of
interchangeability between engines. This engine
has a 147mm bore and a 154mm stroke, and
20 NZ Trucking September 2010 September 2010 NZ Trucking 21

has good torque characteristics with a flattish
torque plateau that stretches from 850/900 to
1650rpm, with peak power running from 1600
to 1850rpm.
What may surprise some people is that the
previous 14-litre Euro 3 engine developed
almost identical horsepower and torque figures,
with a couple of litres fewer capacity. However,
as Keogh points out, “Isuzu wants to be competitive
in the market, and more power and
torque means more cost,” when meeting emission
restrictions.
A couple of years ago they had the option of
a 420 with 1650lb/ft, but that proved not viable
for achieving Euro 4 with that 14-litre engine;
meeting emissions is an expensive exercise, and
the small volumes of our market make it a juggling
act to meet our requirements.
This truck is entry level and targeted at markets
such as the container haulage brigade, who
will appreciate the hi-cube friendly 950mm
chassis height, and be unconcerned about high
performance figures.
The EXY tractor shares much with its EXY530
big brother, including the automated 16-speed
transmission, which had a software upgrade to
better use the performance characteristics of the
re-spec’ed 16-litre engine.
For a start, this engine will rev out to only
1850, and a remapping of the transmission software
makes the most of the engine’s changed
characteristics. The 14-litre engine was more of
a revver by nature, and had a narrower torque
and power band, so if you slipped off it, it
needed some quick gear snatching to keep it on
the boil.
The transmission has had internal updates
as well, to improve reliability and durability.
With an under-stressed large engine, Isuzu must
want the truck’s engine to accumulate some big
distances before needing major work, and we
suspect they’d like the transmission to be just
A new look for the
EXY, but it is still
recognisably an Isuzu.
22 NZ Trucking September 2010 September 2010 NZ Trucking 23

Clockwise from top:
The cockpit layout is
comfortable and easy to
use, with plenty of nooks
and crannies for odds
and sods; easy access is
available to service fulids;
it’s still a three pedal
truck, but that clutch
pedal doesn’t get much
use; the display console is
easy to read, and simple
to keep clean.
as durable. Given that it is basically the same
unit as in the 530, and is capable of handling
2500Nm, we predict durability issues won’t be
an issue.
This particular truck is equipped with a
retarder, an Isuzu magnetic driveline unit which
produces 630Nm of holdback, but it is unclear
if this is to be a standard fitting or an option.
There is an exhaust brake, of which we can only
say it is no Jacobs, but with the retarder, this
combination does a great job of keeping the
brake linings cool.
“There is a drive in Japan to get their trucks
more economical,” says Keogh. “This is the most
European or American-feeling engine so far for
us.” Despite having only 6,000km on the clock,
and being driven by a large number of people
with differing driving styles, the EXY400 had
returned 2.1km/l so far – a surprising figure
considering that distance included a Hastings-
Taupo trip loaded to 44-tonne in front of a
B-train. The engine is spinning at just 1620rpm
at 90km/h, which has to help the fuel figures
as well.
Isuzu New Zealand wanted to give the truck a
good try out to see what it can do, and although
the truck proved it could do the 44-tonne hard
trips, they see the EXY530 as being the best for
that sort of work.
The EXY400 is more comfortable revving in
the low teens on the tacho where it develops
its torque, rather than in the high teens where
Japanese trucks used to rely on whatever power
they had to get by.
It is a world apart from the old Isuzus we’ve
driven, but while the engine performance is
more akin to a Euro than a Japper, they still
have a way to go before feeling like there’s
an American or European engine under the
floorboards. After all, even the bigger-lunged
EXY530 develops only 2,273Nm (1,676lb/ft).
That, while getting closer to the American
engine torque benchmarks, won’t give an ISX
Cummins sleepless nights.
We took a trip through Auckland to Warkworth
while pulling a three-axle trailer loaded to its
39-tonne stickers. It performed well, but it
noticed the hills, as you’d expect. After all, 400
horsepower is 400 horsepower, but the engine
did seem more willing than we predicted from
the spec sheet, and it is a hard haul up this
stretch of the north.
While the transmission seemed to perform better
than the previous Isuzus we’ve been in, we
wouldn’t be surprised if many experienced drivers
operate it in manual for much of the time on
the open road. It can be slotted into auto mode
and left there, but most drivers would probably
be wanting to curb the truck’s tendency to make
unnecessary changes, particularly when cresting
hills. This happens on every automated transmission,
to a greater or lesser degree, and we suspect
the modest power-outputs coupled with 16-cogs
make the EXY400 want to hunt a little. It’s not
as intuitive as you might expect, and if the truck
ever needed to grab a big handful of gears in one
hit, say drop five or more, it will take its time figuring
out what to do and most likely the driver
will need to take over.
Under normal driving, the transmission is
more than up to the job, and as we said, a driver
could leave it in auto all day on most routes with
no problems. It does long steady grades well,
but on tricky routes like the Arthur’s Pass, you’d
need to keep an eye on it.
It’s a no-frills package: there is no hill-start,
the button on the top of the gearstick gives you
the manual/auto function, and a switch above
your head gives power or economy modes.
As Kelly points out, “It’s an aid to drive the
truck.” Almost anybody could jump in and drive
it, he says, and he’d be right. It is like driving a
big Japanese car.
Like anything, it has its idiosyncrasies, and
we’re not sure what to make of the emergency
shift box on the floor. This facility gives the driver
the option of fifth and eighth gears, as well as
reverse, as emergency options to get home or off
the road in case of transmission problems. We
seldom hear of automated transmissions giving
enough problems to warrant its inclusion, but
it’s good peace of mind.
The transmission is a three-pedal system,
which makes yard maneourvering, backing and
other precision driving easy to manage and old
school. However, most automated trucks these
days are headed to two pedals, but it costs more.
Even though it is only used for yard work, it’s
a nice light clutch that offers excellent engagement
feel. There’s little room around the clutch
pedal for the big-footed amongst us, but that’s
nothing new.
The face-lift has seen changes in the grille,
bumper and sun visor, but step inside and you’d
think you were in the 530. There’s plenty of
interchangeability between the two models, and
it seems that Isuzu have got the best of both
worlds with this tractor. It has a great cab, with
plenty of nooks and crannies to hold the modern
truck driver’s daily paper storm, and it’s a large,
light cab with excellent visibility.
As you would expect, 530 pilots get a few
nicer touches such as imitation woodgrain trim,
a six-stack CD player and a hi-roof cab, but
apart from that, the cabs are near-enough to
identical from the driver’s seat. The driver gets
an airbag and Isringhausen 6860 seat (the same
as the 530), a hot/cold storage box, a couple of
overhead lockers and a CD player in the 400. It’s
a pleasant place to spend the day.
Flipping the air-sprung cab is easy, as there’s
an electric motor to do the hard work, as is typical
with a Japanese truck. Once the cab is up,
stand back and marvel at the plumbing. There’s
plenty, a result of the increased amount of EGR
technology bolted to this engine to achieve Euro
4 compliance.
Oil changes are 20,000km apart, and the dipstick
and oil filler hide behind the grille. We were
struck by the tidy cable bundling when we had a
peak at the undergrille layout – it’s quite arty.
Isuzu have managed to price the tractor well
by mixing new technology with the tried and
proven. Braking is undertaken by EBS-compliant
drum brakes – a cost-efficient alternative
to discs – but this EXY is fitted with eight-bag
air-suspension. The bags can be controlled with
a remote controller to raise or lower the suspension
height for loading or coupling and, with the
front parabolic four-leaf suspension, the ride was
quite acceptable, with little body roll. It is on the
stiffer side of the equation and is nicely ironed
out by the driver’s sprung seating.
As we’ve come to expect from Isuzu, the
in-cab noise was down to European levels and
apart from a bit of wind buffing from the mir-
Left top: The get-home box
– an emergency option
should the transmission
strand the vehicle. It’s great
to see it, but we doubt it’ll
ever get much use; it’s an
Isuzu, all said and done.
Middle: Switchery is
minimal, but the truck has
a cross-lock and plenty
of blanks should extra
features be wired in.
Below: New bold styling is
still distinctly Isuzu.
24 NZ Trucking September 2010 September 2010 NZ Trucking 25

ors, the truck was exceptionally quiet for its
price bracket.
The truck has HID headlamps, EBS, ASR,
a power-divider and the digital display gives
plenty of info regarding fuel consumption figures,
with analogue dials supplying the majority
of the remaining essentials.
Overall, the Isuzu continues a tradition of
offering a comfortable, quiet and pleasant work
environment that is hard to criticise considering
the money spent. Given that the truck is almost
identical to its 530 bigger brother – with minor
differences, it’s the same cab, engine and drivetrain
– this new Giga nicely fills the gap that
Isuzu have long been wanting to plug.
The EXY400 has a 24,000kg GVM, and a
GCM of 50,000kg with a curb mass of 7,656
kg, just a tad over the 7,584 kg of the EXY530,
which sports alloy wheels against the 400’s steel
– that partially explains the weight difference.
The extra EGR plumbing and the catalytic converter
to reach Euro 4 probably add a few kilos,
but there’s not much in it.
We can see why Isuzu New Zealand have
been so excited by the arrival of this truck – in
the past, they’ve had to make do by modifying
trucks destined for different end use to satisfy
some of their customers.
With the EXY400 they can tick all the boxes,
and indeed, this tractor is likely to be attractive
to those who cart big boxes. Getting air-bags
and a rear frame height of 950mm on a 6 x 4
tractor isn’t all that easy or common, and Isuzu
are back on track with a model that is sure to
keep the accountant happy, not to mention the
driver.
S p e c i f i c a t i o n s
isuzu EXY400
Tare weight:
GVM:
GCM:
Wheelbase:
Engine:
Capacity:
Maximum power:
Maximum torque:
Air cleaner:
Clutch:
7680kg
24,000kg
50,000kg
4,300mm
6WG1-TCR
15,681cc
Diameter: 15.5”
Transmission:
Rear axles:
Ratio: 3.9:1
Rear axle capacity:
294kW (400hp)
1765Nm (1300lb/ft)
330mm dual element
Twin plate
Isuzu MJX16 AMT
Isuzu RT210
21,000kg
Chassis dimensions: 285 X 85 X 7mm
Front suspension:
Alloy steel parabolic leaf springs
Front axle:
Front axle capacity:
Rear suspension:
Steering:
Brakes:
Park brake:
Auxiliary brake:
Wheels:
Tyres:
Electrical system:
Instruments:
Cab:
Isuzu FO66
6,600kg
Isuzu 8-bag air suspension
Recirculating ball
Full air taper roller
Spring on four rear wheels
Isuzu X-tard
8.25’ X 22.5” 10 stud
275/70R22.5
24V
Speedo, air gauges, tachometer, fuel, cruise
control, diff lock, multi-info display & warnings.
Fully trimmed with vinyl floor coverings, ISRI
driver’s air seat, driver’s side airbag, air
conditioning, hot/cold storage box, radio/CD
player.
26 NZ Trucking September 2010