The Toyota HiLux has reigned as Australia’s best-selling commercial vehicle for the past 16 years, and there are no signs of that changing.

Getting to the top is tough. Staying there is much, much tougher.

Maintaining that dominance for years on end is virtually unheard of.

St George won 11 straight premierships to be rugby league’s greatest team ever. Collingwood ruled from 1927 to 1930 to be the AFL’s best, while Roger Federer’s reign as the king of tennis stretched to 300 consecutive weeks – almost six years in the top spot.

But none of them can hold a candle to the Toyota HiLux. It has held sway as Australia’s best-selling commercial vehicle for the past 16 years. Sixteen!

Let’s put that into context. The last time the HiLux wasn’t Australia’s top-selling commercial, petrol cost 64c a litre, Mark Taylor was our national cricket captain and a little bloke called John Howard had recently been elected to run the country.

People who weren’t born when that streak began are now old enough to drive one.

For the past nine years, the HiLux has also worn the mantle of Australia’s best-selling four-wheel-drive – ahead of the army of off-roaders and soft-roaders so popular these days.

A dozen times, it has topped the Australian monthly sales charts for vehicles of any description.

Earlier this year, Toyota sold its 800,000th Hilux in Australia – more than 40 years after it sold its first back in 1971. It’s hard to imagine those records ever being beaten. Just extended.

Because even after so long at the top, the HiLux continues to get better, thanks to some cosmetic tweaks, a new automatic transmission and upgraded safety rating as part of a mid-model refresh unveiled this year.

We drove the HiLux in its most highly evolved and most expensive form – the range-topping SR5 diesel automatic.

It’s not your typical tradies’ ute – you’re more likely to see an SR5 being driven by the foreman or the boss.

Most workers will more likely be driving one of the 35 model variants now wearing a HiLux badge – from the entry-level $18,000 WorkMate right up to the $54,490 version we tested.

It seems there’s a HiLux for just about any purpose and any price range.

There are three engine options, single and double cab, two-wheel- and four-wheel-drive, ute and cab-chassis, plus a wide range of trim levels.

If ever a vehicle was built to serve two masters, this is it. Work truck during the week, family fun machine on the weekends.

The work side of things I’m not all that well-qualified to assess. For me, the arrival of a car like this in our driveway means little more than the chance to cart a few branches and unwanted items off to the dump.

But clearly the tradies have voted with their feet on the HiLux.

As a family on-and-off-roader, though, it certainly made an impression with us.

It’s been a few years since we last drove a HiLux and it has become a more civilised, refined machine in that time.

Although it stil maintains that hard-working, utilitarian appeal, finishes are prettier and smoother, and the overall cabin ambience much more comfortable.

In its latest form, the SR5 has picked up some handy new features – most importantly a five-star safety rating but also improved display and audio systems, upgraded interior trim and improved fuel-efficiency.

Toyota claims the new five-speed automatic on our test machine has trimmed more than six per cent from the HiLux’s thirst, which now averages 8.7L/100km. The SR5 can be had with a choice of two engines – a brawny four-litre petrol V6 or the four-cylinder, 3-litre diesel that we tested.

Lower-spec models also get the option of a 2.7-litre four-cylinder petrol. The HiLux’s diesel surprised us with its relative smoothness and quiet operation, but that was about it, I’m afraid.

In a market where punchy, fuel-efficient diesels are the rule rather than the exception, the Toyota powerplant lags a bit behind.

It’s a bit sluggish off the mark and never really rises to any great heights of performance. HiLux drivers must be a patient bunch.

At no point in the power band does it come close to matching the performance we’ve enjoyed in rivals such as the Mazda BT50, Ford Ranger or VW’s Amarok (despite its smaller engine).

Even Holden’s Colorado impressed us more. On the positive side, it matches nicely with the five-speed auto (which has been upgraded in this latest model) to deliver smooth, linear progress. On the highway it seems happy enough, although overtaking requires a bit of premeditation.

It delivers well enough on the score of fuel efficiency, too – around town during the working week you can expect about 11L/100km; once the weekend arrives you’ll manage as good as 6.6L/100km on the open road.

Combined average is 8.7L/100km which puts it fairly mid-field in this category. Inside the SR5′s cockpit, the improvement in materials and finishes is evident form the outset. Most impressive is the 6.1-inch display screen – home to the satellite navigation system (yes, on a HiLux) and reversing camera.

iPod and iPhone can be connected via Bluetooth, with controls on the steering wheel. There’s also a “multi-information display” – an LED screen atop the centre stack which shows fuel economy, average speed, cruising range, outside temperature, a compass and clock – all useful stuff for a go-anywhere machine such as this.

Okay, dials and switchgear in the HiLux remain functional rather than fancy, but it all seems to hang together nicely.

Leather seats, big alloy wheels (up from 15-inch to 17-inch in the latest SR5) and a shiny alloy roll-bar in the back all add up to a smart, macho-looking machine.

Handling and ride wise, the HiLux is a mixed bag. It turns assuredly and seems generally well-balanced during most changes of direction, belying its weight and ground clearance.

However, vehicles built to carry substantial loads rarely deliver the most comfortable ride and the HiLux is no exception.

On smooth surfaces it is fine but when the road turns a bit choppy, so does the ride. On that score it probably trails some of its rivals.

Where the HiLux never gives ground, of course, is in the reliability stakes and we’re prepared to bet this model is every bit as bulletproof as those that have come before it.

After all, you don’t stay on top for 16 years for no good reason.

TOYOTA HILUX SR5 DETAILS: Four-door, five-seat dual-cab utility with four-cylinder common rail turbo-diesel engine and five-speed automatic transmission.

TECH STUFF: 3-litre, four-cylinder turbo-charged diesel produces 126kW@3600rpm, 343Nm@1400-3400rpm; five-speed automatic, full-time all-wheel drive.

FEATURES: Five-star safety rating with stability control, traction control, electronic brakeforce distribution and brake assist; satellite navigation, electric windows and mirrors, climate-control air-conditioning, reversing camera, cruise control, leather trim, automatic headlights and wipers.

THIRST: 8.7L/100KM (combined average).

VERDICT: Unstoppable – on-road, off-road and in the showroom.

BOTTOM LINE: $54,490 (plus on-road costs).