Isuzu’s F series gets fitted with new 4HK1 and 6HK1 engines
Isuzu Australia (IAL) lifted the curtain on its new F-Series to the Australian medium-duty truck market, boasting two brand new engines, with one Isuzu claims to be the cleanest Japanese medium-duty diesel engine available down-under.
IAL chief engineer Simon Humphries says the engine technology supporting 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,” he says.
The completely redesigned 4HK1 is a 5.2 litre, four-cylinder, two-stage turbocharged and intercooled engine is available in two power ratings, a 154kW (207hp) and the more powerful 177kW (237hp).
The 4HK1 diesel engine generates improved power and torque ratings, with the 207hp models, the Isuzu FRR, FRD and FSS 4×4 all producing 726 Nm of torque, a 14 per cent increase in peak torque, and a 45 per cent torque increase at 1,000 revs per minute because of the new two-stage turbo technology.
The new 4HK1 replaces the former six-cylinder engine in the 177kW models, yet offers the same peak power and up to eight per cent more torque at 765Nm of torque.
Unique to the low displacement, high horsepower 4Hk1 engines is the Idle-Stop System (ISS), improving fuel economy by resting the engine when the vehicle comes to a halt.
Available in all 4HK1 4×2 models except with the power take-off unit, the ISS feature improves fuel economy by 3 per cent Isuzu says, and is activated in a manual transmission vehicle when the vehicle is stationary and in the neutral position with the clutch released.
With the Isuzu automated manual transmission (TC-AMT), activating ISS requires firm pressure on the brake pedal engages the ISS.
The 4HK1’s exhaust and emissions system has gained an external injector for the diesel particulate diffuser (DPD) to treat exhaust gas.
The F-Series 4HK1 engine.
Isuzu also unveiled its new 7.8 litre, six-cylinder water-cooled, direct injection diesel engine, the 6HK1 with the ‘Diesel Oxidisation Catalyst’ (DOC).
The 6HK1 DOC is available for the Isuzu FRR, FSR, FSD, FTR and FTS models equipped with Isuzu’s own air-assisted six-speed manual transmission and the Allison 2500 Series automatic transmission.
The new 6HK1 diesel engine generates 191kW (256hp) and 761Nm of torque, and is equipped with torque convertor with a lock-up clutch, exclusive to the Isuzu F Series models with 6HK1 DOC engine.
Isuzu’s Diesel Oxidation Catalyst (DOC) system means no selective catalytic reduction or DPD regenerations for models, creating 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, which Isuzu believe will be popular with customers.