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Diesel cars ain't what they used to be

Hyundai’s recent decision to offer diesel alternatives right across its New Zealand range underlines an important trend – one that some people would rather not know about.

It’s the growing use of diesel engines in passenger cars and light SUVs. There’s a bit of a Kiwi mindset that diesel’s okay in trucks and utes and big 4WDs, but that’s where it should be left.

Experience with some of the poorly maintained, used import Japanese diesel cars that have entered the national fleet over the last couple of decades hasn’t helped change that point of view.

But today’s diesels make excellent car powerplants and, despite the diehards, demand is growing. Companies without diesel models may even regard themselves as disadvantaged.

Subaru New Zealand, for one, can’t wait to get its new horizontally-opposed diesel, but the production line is being sucked dry by Europe.

Same for Nissan – keen to get the diesel version of its new X-Trail SUV.

In luxuryland, whose inhabitants can afford whatever they want, some of the most popular BMWs, Audis and Mercedes are now diesel powered.

So should you be considering a diesel as your next car?
What about costs?

Will neighbours point and snigger?

The advent of computer controls, high-pressure common-rail fuel injection, and particulate filters have transformed the diesel as a passenger car motor.
Those first two items improve the already good fuel economy and do great things for refinement, drivability and output.

In concert with the particulate filter, they allow diesels to meet stringent European emission regulations.

Most people who haven’t driven a diesel car for years will be impressed by how smooth and quiet they are – at least from the inside.

From the outside, there’s still no doubt which type of engine is under the bonnet, especially when starting cold on a winter morning.

Most of today’s crop of passenger diesels are turbocharged, and while their power is still likely to be less than a petrol equivalent, torque will not only be significantly better, but available much lower in the rev range.
In real-world driving, this means less gear changing, great tractability and quick passing times, possibly quicker than the petrol version. In some situations, the diesel version of a car may be quicker on a cross-country trip than the petrol.

The torque advantage means that diesels make very good tow vehicles – this has always been a forte.

Diesel will usually offer better fuel consumption than a similar-sized petrol, but no longer by the wide margin that was usual a few years ago. It’s not that diesels are getting worse, but that petrol motors – particularly smaller-capacity ones – have become so much better.
And remember, when you see the lower price of diesel at the filling station, the bothersome Road User Charges fee goes on top, narrowing the gap.

These days, buyers often choose a diesel for its driving characteristics rather than for its ability to travel the longest distance on a litre of fuel, or its cost.

There is a widely held belief that diesels will run for much higher distances before giving trouble. Some of this is probably based on the amazing lasting ability of diesel truck engines.

In that industry, a quarter of a million kilometres motor is regarded as being just nicely settled in. But car diesels can be a different story, especially those that are conversions of petrol engines. And while the trucking industry generally adheres to a comprehensive maintenance programme, private owners may be less fastidious.

A disincentive to buy a new diesel car may be its price.

Many, though not all, manufacturers charge a premium for their diesel models, legitimately claiming higher manufacturing costs. Check out how much fuel you could buy with the difference between a petrol and diesel model.

However, the price differences are likely to close, if not be eliminated, in the not-distant future.

Servicing costs used to be higher for diesels, though today’s engines tend to be similar to petrol for servicing costs, aided by generally longer oil and filter change intervals.
I have been driving a diesel vehicle for 10 years now and would find it hard to change back to petrol.

The combo of good mileage, reliability and great drivability becomes addictive.
Take that as a recommendation!

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