Isuzu KB300 TDI LX DC 4×4

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Double cabs have come of age...

THERE were days when bakkie-based double-cabs were considered to be “a poor man’s SUV”, not least because of the limitations of the concept –separate chassis, compromised cab space, cart spring suspension, and commercial vehicle-style interiors among them. But, generally, they were less expensive to buy than dedicated sport-utilities, so providing you could adapt to the basic configuration, suitable transportation for the pursuit of an active lifestyle was more attainable. Delta has been a major player in the segment for many years, even so far as producing an SUV derivative of its Isuzu KB pick-up – the Frontier. However, as Nissan found with the Sani, this bodystyle proved not to be particularly popular, suggesting that double-cabs have become universally acceptable as is.

Nowadays, though, double-cabs are far more upmarket than their forbears. For 2002 model year, Delta has freshened-up the whole Isuzu line-up, but the most significant change is the replacement of the KB280 derivatives with the KB300, and the version incorporating the most improvements is the flagship LX 4×4 DC, which was submitted to CAR for test prior to launch. With the KB280 considered by many as a benchmark in its class, we were naturally interested to see how the newcomer stacked up.

The KB300 nomenclature tells the first story: the bore and stroke of the previous 2 771 cm3 four cylinder direct injection diesel engine have been increased, raising cubic capacity to 2 999 cm3. In addition, there is a larger capacity radiator, and the turbo has been complemented by an intercooler to help improve the combustion process. A large scoop has been grafted into the centre rear of the bonnet to feed air to the substantial intercooler, which lowers intake air temperature by up to 23 per cent. With the greater swept volume and chilled charge air, power has increased by 30 per cent from 74 kW at 3 600 r/min to 96 kW at 3 800. Peak torque has improved markedly too, up by 15 per cent from 230 N.m at 2 200 r/min to 265 N.m at 2 000.

Replacing the 280’s mechanical diesel injection pump is a Bosch VP44 electronic radial plunger distribution pump, which is controlled by an ECU monitoring data from sensors mounted in and around the engine. Benefits of the new system include more accurate fuel injection, resulting in optimised fuel economy and lower exhaust emissions, improved wide-open throttle/overtaking acceleration performance, and better high-speed cruising ability, especially at altitude and at high ambient temperatures. Delta claims the KB300’s overall trip fuel consumption to be 11,7 litres/100 km, which is a fraction higher than that of the KB280’s 11,3 – hence its use of the word “optimised”. Supporting Delta’s claim, CAR’s tank to tank consumption figure over the test period was 11,51 litres/100 km.

Gearing is different from before. The MUA5C gearbox, as fitted to the V6 petrol-engined KB320, has been adopted because of its greater torque capacity (265 N.m) over the KB280’s MUA5S ’box. For the same reason a beefier rear axle is used, which also has a different final drive ratio, a taller 4,3:1 in place of the previous 4,555:1. Last, but certainly not least, “shift on the fly” engagement of 4wd – at speeds up to 96 km/h – is now possible, a feature that is standard only on this model. And to help overcome extreme driving conditions, a diff lock is fitted that is engaged by a switch on the facia.

Mechanically, then, the KB300 is more sophisticated than the average double-cab but, of all the current local pick-up ranges, the KB is now the longest running. However, its looks continue to appeal. Fixtures and fittings are, naturally, designed for function rather than form, but it is only the lack of soft-touch plastics and the utilitarian switchgear that serve as reminders of the vehicle’s light commercial origins. In mitigation, the KB300 LX is not – and does not pretend to be – a pukka SUV. Viewed as such, the average-car-like interior is entirely acceptable.

The front seats are a surprise. Upholstered in leather and styled into panels with contrasting stitching, the chairs have only basic fore/aft and backrest angle adjustment, yet were rated comfortable and supportive by all the testers. For passengers in the back, the rear bench is stylised to match the front seats, and, relatively, is as comfortable. Legroom is totally dependent on the position of the front seats, but a quartet of average-sized adults will not feel unduly cramped. Access to the back is tight due to the wide B-pillar and limited door opening – a generic double-cab problem – but steps are attached to the tubular “running boards” to aid entry/exit.

LX trim means the king of the KBs is well appointed. Remote central locking is fitted and all the locks snap shut once on the move: the action can be released by lifting the driver’s door knob. Also standard are a rake-adjustable steering wheel, air-con with four-speed fan, a radio (irritatingly fiddly to operate) with separate 4-CD shuttle mounted in the hangdown console, uncharacteristically flashy chromed exterior mirrors with electrical adjustment, remote fuel flap release, maplights on the ’screen header rail, and an instrument backlighting rheostat. The cab’s tinted glass area is generous: the windscreen has a shaded upper band, and the backlight is openable. All door windows are power operated and descend fully, the driver’s with one-touch down.

Being a 4×4, there is the usual array of bundu-bashing equipment including a tubular bull bar (flanked by auxiliary main beam driving lights) that incorporates a skid grid extending underneath the bumper, a dual roll hoop in the loadbox, and a tubular rear bumper/step with tow hitch beneath the tailgate. All are painted grey to match the front bumper insert, bodyside mouldings and wheelarch flares. The loadbox tonneau cover is secured with a strap-type tie. Mudflaps are fitted front and rear.

Lots of kit, then, but how does it go? A study of the test results reveals that it goes well, thank you. Compared with the brand new and most-powerful-in-class Nissan Hardbody three-litre turbodiesel, at 14,84 seconds the KB300 takes only three-tenths longer for the 0-100 km/h sprint, and has practically the same top speed of 158 km/h.

In-gear acceleration is not significantly inferior, either. At idle, and when stretched, the KB’s engine clatters in typecast diesel fashion, but press the stiff accelerator towards the floor and it smoothes out to provide very relaxed cruising. Gradients are now easier to mount: our crew was followed up a test hill by a KB320 and the driver flagged us down to comment on how impressed he was with the TDI’s climbing power. Carrying some pre-cast concrete garden furniture in the large (1 505×1 530×447 mm) loadbox appeared to have little effect on the engine’s hauling ability.

Steering is a little twirly at 4,1 turns from lock to lock, despite power assistance. Nevertheless, the KB offers secure handling, almost neutral in

2wd, moving towards typical understeer in 4wd. Ride quality continues to be excellent, traversing dirt-road corrugations with ease and absorbing rougher surfaces with equal aplomb. Once we had bedded-in the brakes, stopping ability was consistently good with no suggestion of lock-up when unladen. Rolling on 245/75 tyres fitted to attractive 15-inch alloys, we noticed the test vehicle’s odo was overly optimistic.