The best-selling vehicle badge in recent years isn't found on the back of a car but on a pickup truck. With sales exceeding 10,000 units practically every month, the Toyota Hilux Vigo is the four-wheeler of choice for Thais.

That isn't surprising considering the many positive attributes the Vigo boasts over its rivals since it was launched in its current generation in 2004, aside from other crucial factors such as a solid resale value and widely available spare parts and authorised garages.

The best offering in the Vigo lineup is none other than the four-door double-cab which has set standards in packaging, smooth powertrain and car-like driving characteristics.

So well accepted is the Vigo that Toyota has hardly bothered giving it any major technical updates over the past eight years. The only revision came in the guise of two facelifts _ one in 2008 and another in 2011, the latter seeing the comical "Champ" name added to the already long badge.

Due to be replaced in less than two years, it was only last month that Toyota Motor Thailand decided to give the Vigo some mechanical tweaks _ a little late, some may think.

But the official line from the country's leading marque is that Euro 4 emission standards came into effect in Thailand at mid-year, which goes some way to explaining why it didn't hurry with the technical update.

But the Vigo rules the Thai market after all. We bet that if it was a third-tier player such as Ford or Mazda, the case would have been different.

So what exactly has improved under the Vigo's bonnet? First, the 3.0 litre turbo-diesel motor's power has been upped from 163hp to 171hp, while torque has risen from 343Nm to 360Nm.

The idea isn't to top the performance race, as Ford and Mazda are doing with their 200hp 3.2 litre engines in the Ranger and BT-50. Instead, it was done in the interests of cleaner emissions and reduced fuel consumption.

To this end, there's a more efficient fuel injection system and a five-speed automatic transmission in place of the old four-speeder. Once again, the Vigo isn't winning the numbers race with the Ranger and BT-50, both boasting six-speed auto 'boxes.

Nevertheless, the Vigo is still a fine performer when you take the whole market into account. The engine/gearbox combination is still one of the smoothest, most responsive and most frugal.

While we hardly ever managed to see the Vigo's computer reading 12kpl in the past, the average figure rose above that level comfortably many times in this improved version we drove in the South earlier this month.

We'd be telling you a fib to suggest that the Vigo is now a faster pickup on the move. As said earlier, let's just say the marginal increase in the number of ponies has been done for the sake of better efficiency.

This is to say the Vigo still has the performance and economy to stay ahead of many of its rivals, but what it now lacks is the sheer refinement found in the five-pot motors of the Ranger and BT-50.

The Vigo's chassis hasn't changed for 2012 _ it already does a pretty good job in the delicate balance between handling and ride. Toyota believes that few double-cab users move around bank vaults, so the focus is tipped slightly to ride comfort.

Ford has stuck with principles of cargo hauling, explaining why its ride is probably the firmest of all the pickups now on sale. But the upside of this is great handling, even under load. However, it seems that Mazda has come up with the best compromise in its BT-50.

But one area where the Vigo's chassis is showing its age is in body control. The BT-50 feels more planted and composed on tarmac.

And speaking of the Vigo's rivals _ which have taken the metal race to new heights _ they are the biggest around and sport vast cargo beds, if that's going to matter to most buyers.

Yet, the Vigo still has sensible proportions _ it's sufficiently big but not too cumbersome to drive on tight roads. The Vigo's cabin still remains a valuable lesson for rivals to heed.

It has the most comfortable rear quarters, thanks to easy entry/exit, perfectly angled seat cushions and ample legroom.

But it is also here where weak points are pronounced.

Like the exterior, the interior design is weary and bland. Plus, the plastics feel drab and are more suitable for dressing up lawnmowers.

But overall, the Vigo has aged well and is not that old at heart. The technical changes it has received this year are certainly welcome, if not effective enough to make it a class leader.

And for the first time, the Prerunner (2WD-only and high-riding body) gets an automatic option when all of its rivals have offered it for years. In 3.0 litre form, as tested here, the Prerunner costs 918,000 baht.

OUR FINAL RECKONING

If this was a comparison test between all seven double-cab pickups in the Thai market, this is how we would rank them.