News & Media


“The Isuzu new 4HK1 in the 2016 F Series can lay claim to being the cleanest medium-duty Japanese diesel engine on the Australian market today”

With its long-standing dedication to the road transport task in Australia, Isuzu Australia Limited (IAL) has raised the bar yet again with an innovative new approach.

Australia’s favourite tried and tested medium-duty champion, the Isuzu F Series*, is now available with two new and very diverse driveline technologies.

From now on, Isuzu medium-duty truck customers have a genuine choice depending on their application and preferences.

More choice 

Operators can now specify an intelligent new F Series with a low displacement, high torque four-cylinder turbocharged and intercooled diesel engine – featuring the latest technology from Japan – mated to a torque converter equipped automated manual transmission (TC-AMT).

Alternatively, there’s a new no-fuss, six-cylinder Isuzu 6HK1 engine with maintenance-free Diesel Oxidation Catalyst (DOC) for an ultra-reliable, low maintenance solution.

Whether it’s waste and refuse, cold chain logistics, traditional road freight or something out of the ordinary, the intelligent new Isuzu F Series range covers even more applications than the previous line-up. Just as welcome is the fact it also meets the specific needs of a whole host of niche applications.

A fresh approach 

IAL Chief Engineer, Product Strategy, Simon Humphries, said the engine technology underpinning the range represents a more cohesive and adaptable approach.

“With the new 2016 F Series range, we’ve developed the driveline technology to cater to an ever-changing market.

“We’ve listened closely to the requirements of our customers and taken note of the global trend toward lower displacement engines throughout the automotive world,” Mr Humphries said.

“Supplying niche applications areas with a fit-for-purpose, reliable engine solution while conserving green credentials was a major focus in developing this new engine technology.

“Importantly, this new range enhances a quality that Isuzu has always been known for – our ability to cater to broader market needs – while also filling those niche applications where ‘near enough’ will never cut it.”

Isuzu’s new 4HK1 engine technology

Isuzu’s new 4HK1 represents brand new Japanese engine technology and there’s nothing quite like it in the Australian medium-duty truck market right now.

The new 4HK1 is a low displacement, high horsepower diesel engine generating impressive power and torque ratings.

The 5.2 litre, four-cylinder, two-stage turbocharged and intercooled engine is available in two power ratings.

The 154 kW (210 PS) variant produces 726 Nm of torque; its more powerful counterpart posts 177 kW (or 240 PS) and a handy 765 Nm of torque.

The 210 PS variants include the Isuzu FRR, FRD and FSS 4×4 with GVMs spanning 10.7 to 11 tonnes. In these models, peak torque is increased by 14 per cent, and the new two-stage turbo technology provides 45 per cent more torque at 1,000 revs per minute.

The 240 horsepower models include the FRR at 11 tonnes GVM and FSR at 12 and 14 tonnes GVM respectively. For these models, the new 4HK1 replaces a six-cylinder engine, yet offers the same peak power and up to eight per cent more torque.

New two-stage turbo 

The addition of a clever two-stage turbocharger to the new 4HK1 incorporates a combination of low and high pressure turbochargers, which increases torque levels at low engine speed.

In addition to the two-stage turbocharger, almost every part of the previous Isuzu 4HK1 has been revised in the pursuit of a clean, green engine with excellent performance.

Common rail injection pressure is increased by more than ten per cent to 200 MPa, the injectors themselves have an increased number of nozzles, the piston shape is changed, the Exhaust Gas Recirculation (EGR) system is more accurately controlled, the intercooler size is increased by ten per cent and the intake cam profile is revised.

Isuzu F Series models fitted with the new 4HK1 engine also benefit from the inclusion of Isuzu’s Idle-Stop System (ISS), which works to produce impressive fuel economy figures by cutting engine use when the vehicle comes to a stop – for example, at traffic lights.

ISS is now standard in new 4HK1 4×2 models, except the model equipped with an engine driven power take-off (PTO) unit, and it helps both the 210 PS and 240 PS variants deliver class-leading fuel economy.

Recent analysis by Isuzu Australia shows that trucks in this class are idling at an average of 50 per cent of time in operation – so good fuel savings are anticipated from these models.

Isuzu’s data, relevant to the domestic market, confirms a seven per cent overall fuel saving in the new 4HK1, with the ISS system making-up three per cent of that total.

Depending on the chosen transmission, ISS works slightly differently in manual and automated manual transmission (AMT) modes.

Should a manual transmission be required, ISS is engaged when the vehicle is stationary and in the neutral position with the clutch released. The Isuzu TC-AMT requires nothing more than firm pressure on the brake pedal to engage ISS and start saving fuel.

Isuzu’s new 4HK1: Clean and green

An external injector for Isuzu’s diesel particulate diffuser or DPD system has been added to the new 4HK1 exhaust and emissions system.

The new external injector eliminates oil dilution through the regeneration process.

Both Euro VI and PNLT standards are expected to be included as equivalents for ADR 80/04, the next heavy vehicle emissions standard under development.

When compared with Euro V emissions limits, Japan’s Post New Long Term (PNLT) standards require a reduction in nitrogen oxides (NOx) by 65 per cent and in particulate matter (PM) by 50 per cent.

Add ISS and low displacement technology to the mix and the Isuzu new 4HK1 can lay claim to being the cleanest, most advanced medium-duty Japanese diesel engine on the Australian market today.

Isuzu 6HK1 with DOC

Complementing the new 4HK1 offering is Isuzu’s advanced 6HK1 DOC, Euro V engine, tailored for specific vocational applications.

The 7.8 litre water-cooled, six-cylinder direct injection diesel engine generates 191 kW (260 PS) and 761 Nm of torque across a wide rev range, so there’s certainly enough grunt under the right foot, regardless of the task at hand.

The 6HK1 electronic control common rail injection system features ten per cent higher injection pressure and a new injector design, improving combustion efficiency. This equates to higher engine performance, lower emissions and lower fuel consumption.

The 6HK1 DOC is available in various Isuzu FRR, FSR, FSD, FTR and FTS models equipped with Isuzu’s own air-assisted six-speed manual transmission.

A two-pedal option is also available, with the Allison 2500 Series automatic transmission – featuring a torque convertor with a lock-up clutch – exclusive to the Isuzu F Series models with 6HK1 DOC engine.

The new 6HK1 with DOC has also found a home in a brand new model to hit the F Series line-up – the Isuzu FVR/D – available with a choice of transmissions, including the Allison MD 3000 auto or the ZF nine-speed air assisted manual.

Diesel Oxidation Catalyst (DOC)

The exhaust and emissions system attached to the 6HK1 now comes fitted with a Diesel Oxidation Catalyst (DOC), meaning no selective catalytic reduction or DPD regenerations for models so fitted. This is anticipated to be very popular in vocational applications.

It’s the only medium-duty engine on the market with neither a diesel particulate filter nor SCR, meaning less driver intervention and less frequent service intervals.

An important end-use feature of the DOC system is its suitability for applications where high idle times, high PTO use and frequent stop-starting are a feature. Council service and elevated work platform trucks are perfect examples of the applicability of the 6HK1 DOC.

Fit-for-purpose engine technologies

IAL National Sales Manager, Andrew Harbison, said Isuzu’s new 4HK1 engine and its robust 6HK1 DOC cousin underpin a range that’s been built to fill as many end uses as possible, while delivering power, fuel economy and effective emissions control.

“Isuzu’s engineering approach has always been straight forward.

“Whatever it is we’re working to develop or refine, we keep the product – and its end use – very much at the heart of the process,” Mr Harbison said.

“With regards to these two distinct engine technologies, there’s no ‘fluff’.

“While quite different in terms of ultimate application, they’re both highly dependable and that’s what Isuzu is known for – honest, reliable, fit-for-purpose products that stand the test of time.”

*Transport Industry Council (TIC) T-Mark data, Full Year 2008–2015 inclusive

For further information, please contact:         
Jeff Birdseye                                                    
Marketing Manager                                            
Isuzu Australia Limited                                      
Phone: 03 9644 6666

For Isuzu Truck Releases and Photos:
Arkajon Communications
Phone: 03 9867 5611