ONE short drive in the new Grand Cherokee is all it takes to realise the German influence on Jeep's new SUV flagship runs far deeper than its Mercedes-style scalloped headlights.

A tough Outback launch drive on the Gibb River Road between Broome and Fitzroy Crossing showed it's stiffer, tougher and more capable away from the blacktop than before.

But even before we'd left Broome, the crisp new variable-ratio rack-and-pinion steering, more comfortable interior and better composed on-road behaviour showed this is a Grand Cherokee like none before it.

Direct, responsive and with a turning circle as tight as some small cars', the new steering is the first surprise.

Composed and confidence-inspiring, the Grand's straightline steering feel would make some smaller vehicles feel inferior, and makes it feel far smaller both in the carpark and at top speed.

Combined with firm new suspension all round, the new Grand turns in, corners and changes direction a lot more like a BMW X5 than its predecessor.

Though there was little opportunity to push the Grand hard into twisting bends at the launch, the sharp steering and minimal bodyroll make it clear this Jeep achieves a new level of on-road dynamics.

While none of this appears to affect ride quality too adversely, some of the Gibb River Road's badly corrugated section had us searching for the 'sweet spot' to escape a nasty suspension resonance.

Beefier new brakes only increase the new Grand's road-holding ability and, if the gamut of active safety features (including ABS, EBD, traction control, stability control and electronic rollover mitigation) fails to keep you on the road, there's a plethora of airbags including full-length side curtains.

The choice of two effective permanent four-wheel drive systems and a simple lever-actuated low-range mode retains the biggest Jeep's hallmark off-road ability, with all vehicles easily traversing the 17km of deep, soft sand of WA's Cable Beach.

The new chassis is claimed to be 60 per cent stiffer than before, and felt every bit of it as it crashed confidently through unexpected washaways at over-ambitious speeds, time after time.

Of course, the new Grand's on-road competence is aided in no small measure by Jeep's proven 4.7-litre V8, bookended by a 3.0-litre turbo-diesel that's yet to appear and the stonking new 5.7 HEMI V8.

While the oil-burner was unavailable at launch, both V8s sound glorious at full flight and offer bristling off-idle acceleration, especially from standstill.

There's no shortage of overtaking urge either, and even at constant highway speeds above 130km/h the MDS-equipped HEMI returned fuel consumption figures consistently in the respectable 16L/100km range.

However, some testers saw in excess of 24L/100km during hard usage.

Either way, there's no doubt the diesel will be far more efficient and, with the same impressive 3500kg towing capacity, should attract at least a third of sales.

The host of interior improvements is too extensive to detail here, but items like thicker noise damping materials, a better sealing pack, wind tunnel-tested mirrors a new air-conditioning blower and improved air-flow combine to make the new interior a quieter and more comfortable place.

Two days of Outback road dust failed to penetrate the new cabin.

And while supportive new Benz-sourced power seats banish the American sofas of Grands gone by, for our money they're still mounted too high.

Combined with an intrusive AU Falcon-like A-pillar, the new Grand is not as easy to enter/exit as it could be and may leave tall drivers wanting for extra head room - especially in vehicles fitted with a sunroof.

The other major blight on the otherwise well conceived and less-cluttered Grand Cherokee interior concerns dash materials that are hard to touch and look a little out of place in a $50,000-plus vehicle.

A woodgrain console surround and armrest trims replace the Laredo's carbon-look highlights, but do little to lift the look.

While we're complaining, there's no telescopic steering wheel adjustment, the LCD information panels are hard to read in direct sunlight, only the driver's power window scores an auto-down function, there's no proper driver's footrest and the handbrake remains on the wrong side of the transmission tunnel.

That said, the Grand's interior remains functional and flexible, offering a useful programmable trip computer, four cup-holders, practical A-pillar-mounted grabrails, deep door compartments and a 60/40-split rear seat that provides access to a cavernous and clever cargo hold.

Here, there's no fewer than eight tie-down points, numerous 12-volt power outlets, a cargo cover, three child restraint points, rear side compartments and a handy reversible centre floor section to prevent the shopping rolling around.

Quiet, refined and now highly capable on bitumen, it appears Jeep's desire to target the vast majority of SUV buyers who spend most of their time on sealed roads has paid big dividends - without sacrificing off-road ability.

Much larger but only 40kg heavier on average, the Grand retains most of the vital statistics that matter off-road, including 209mm of ground clearance, respectable approach and departure angles and formidable wading capability.

But it's the wider footprint, stiffer bodyshell and vastly improved steering and suspension systems that make the big difference on the road.

It's not perfect, but with sensible pricing and a choice of engines to suit plenty of buyers - and a hi-po SRT-8 halo model to come - the Grand Cherokee should easily find its niche in the crowded luxury SUV segment.