Ford Australia has been pleasantly surprised by the popularity of the diesel V6 in the SZ Territory SUV.

VFACTS figures for the latter half of 2011 reveal that as much as 70 per cent of Territory sales (from July through to December inclusive) were diesels.

"There's been a strong skew to higher end — Titanium — as well... it's a good result," said Ford Brand Communications Manager Neil McDonald.

But it does throw into question the viability of the inline petrol six-cylinder that used to be the exclusive engine powering the Territory. From the first full month on sale (June 2011), the diesels have outsold petrol variants by a considerable margin. That was to be expected for the period immediately following the SZ model's launch, as we explained in an earlier story, but the sales split in favour of diesels shows no sign of abating — something that Ford didn't anticipate. As of the end of 2011, petrol Territory sales stood at 6759 (including SY II models sold during the first half of the year), diesels accounted for 7107 after less than seven months.

The petrol variants hardest hit by the migration to the SZ model — and introduction of diesel power — have been the high-grade (Ghia/Titanium) level of trim and the base TX model. Only the mid-range petrol-engined Territory TS is hanging in there. 

Although the popularity of the diesel casts a cloud over the business case for the Geelong-built inline six, Ford shows no signs of concern about the well regarded six-pot.

"The I6 is a pretty good engine; I think there'll always be a component [of buyers] for that particular engine in the line-up," said McDonald when motoring.com.au spoke with him last week.

"Territory's probably getting momentum too, in the market, with awareness of diesel. [The sales skew in favour of diesel has] probably gone on a bit longer than maybe we thought, but the expectation would be that it will probably settle down to some equilibrium at some stage."

McDonald acknowledged that forecasting the ongoing sales rate for Ford's alternative engine options — for both Territory and Falcon — is not an exact science.

"It's probably the same with EcoBoost [Falcon]," he said. "It's very hard to know [how that will sell]. It's too early to tell; the [car] hasn't even gone on sale."

"The initial response we got from media was pretty encouraging; it's the sort of thing [where] we'll have to wait to see what fleets think and how it fits into their structures. Also the 'Buy Australia' requirement and CO2 and fuel economy are big things with fleets these days."

McDonald says that offering EcoBoost and the Territory's diesel isn't part of a broader plan to phase out the petrol six and close the plant assembling it, as had been proposed in the past. Manufactured by Ford in Geelong, the engine has previously been a candidate for the axe, with an earlier Ford Australia president, Tom Gorman, announcing a plan to import an American-built 3.7-litre V6 to power the Falcon and Territory. That plan was subsequently rescinded, but Falcon sales have shown a steady decline since — not offset by Territory gaining ground following the introduction of the new model.

"Bob [Graziano, Ford Australia president] has been quite clear in saying we want to offer a suite of engine options across the model range," says McDonald. "Obviously with EcoBoost and I6 and EcoLPI — plus the diesel for Territory — it's a pretty good combination."

Nonetheless, EcoBoost will cannibalise six-cylinder sales if it's effectively comparable to the six, but costs less to run. McDonald argues that Ford is following in the footsteps of global manufacturers, providing buyers with a downsized-displacement choice, as well as sticking with the big bangers.

"The Europeans are offering down-sized engines as well as super-performance V8s," he said. "You've got to canvas the wide spectrum of your options. The more options you have, the more chances of getting people into your cars. You can't say 'oh well, because that one's a success we'll drop the other one'."

At least the introduction of Euro 5 emissions legislation is less likely to hamper efforts to keep the inline six alive and in production at Geelong, since the announcement in Detroit last month, of $103 million of government funding.

But at the end of the day, consumers also have to buy cars powered by the engine for it to remain in production.

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