German Car Zone

It's a Diesel, but It's Also a Jaguar


This is the most important car in Jaguar's history. It's the 2008 Jaguar XF 2.7D — that's "D" as in diesel. And if Jaguar is to survive and prosper in Britain with gasoline prices now reaching $9 per gallon, then this car simply has to succeed.

And just as important, a diesel luxury sedan like this could reinvigorate Jaguar in the United States.

Back in the early 1990s, however, Jaguar's senior management convinced themselves that no one would ever buy a diesel Jag. The benefits of diesel, they opined, ran counter to Jaguar's brand values and thus could be safely ignored. And so, with astonishing naiveté, they sat back and watched as BMW, Mercedes and finally Audi developed ultra-sophisticated diesels that seduced those Europeans looking for executive-class transportation. Only when the Mercedes-Benz S320CDi began to outsell the gasoline version of the S-Class did Jaguar's leadership awaken to the possibilities of a premium package with diesel power.

Today — in Europe, at least — the diesel models are the most important in the Jaguar range, and it is the frugal 2008 Jaguar XF 2.7D that must lead the fight against the German might.

A Smokin' V6

The 2008 Jaguar XF 2.7D features the AJD-V6, a twin-turbo V6 introduced by the 2004 Jaguar S-Type. It has its roots in the Lion engine family (a 2.7-liter V6 and 3.6-liter V8), which Ford's Dagenham Diesel Center put into development in 1999 for use by both Ford and the French PSA (Peugeot and Citroën) concern. The 2.7-liter V6 has found its way to Jaguar in twin-turbo form and to Land Rover in single-turbo guise.

This is a very modern diesel. The long-stroke (81.0mm bore by 88.0mm stroke) V6 displaces 2,720cc and the DOHC cylinder heads feature four valves per cylinder. It employs common-rail direct injection with fast-acting piezo electric injectors and a drive-by-wire throttle. The block is made from compacted graphite iron (CGI) and the cylinder heads are made from aluminum, which help make this the lightest diesel of its size and type, just 33 pounds heavier than a comparable gasoline-fueled V6, Jaguar says. There are twin variable-geometry turbochargers with electronic control and an air-to-air intercooler, and the compression ratio is 17.3:1.

Refinement is also part of the AJD-V6's program. To reduce noise, the engine features a double-wall oil sump and well-isolated cam covers made from composite. The V6 configuration also takes the sting out of the vibration from high-compression ignition, plus unique, dual-isolated engine mounts and a dedicated final-drive assembly help absorb some of the torque reaction.

The upshot of all this technical trickery is an engine that develops 204 horsepower at 4,000 rpm and 320 pound-feet of torque at just 1,900 rpm. This betters the 190 hp of the similarly priced Mercedes-Benz E280 CDi and the 192 hp of the BMW 525d.

Performance Like a Jaguar

The on-road performance of the XF 2.7D gives the lie to anyone who argues that diesel propulsion is inherently "un-Jaguarlike." If we accept — as is the conventional wisdom — that Jaguar's brand values are all about torque, refinement and effortless performance, then a modern turbodiesel fulfills these requirements at least as well as the gasoline alternatives.

The performance of the 2008 Jaguar XF 2.7D is competitive. Jaguar claims acceleration to 60 mph in 7.7 seconds on the way to the quarter-mile in 16.0 seconds. This compares favorably with the 7.9-second acceleration to 60 mph and the 16.1-second performance in the quarter-mile of the XF when equipped with the 240-hp 3.0-liter V6. But of course the diesel XF is comfortably outperformed by the 6.2-second time to 60 mph and the 14.9-second quarter-mile mark achieved by the XF with its 300-hp 4.2-liter V8, while the 5.1-second time to 60 mph and the 13.8-second mark to the quarter-mile of the supercharged 4.2-liter V8 is in a different league. The XF 2.7D weighs 3,904 pounds, about 200 pounds more than the XF 3.0 V6 but only about 50 pounds heavier than the XF 4.2 V8.

When it comes to midrange performance, where the torque output becomes more relevant, the 2.7D offers a convincing surge of thrust. It accelerates from 50 to 70 mph in 4.4 seconds, which compares well to the 4.1-second performance of the gas V6, the 3.3-second mark of the 4.2 V8 and the 2.4-second time of the supercharged 4.2 V8.

Refinement Like a Jaguar

The diesel installation is superb, delivering exceptional refinement throughout the rev range. Even at idle, you must listen hard to identify this as a diesel, while it's all but silent at highway speeds.

This engine also proves an ideal foil for the ZF-built six-speed transmission. The gearchanges are comfortably slurred and the semiautomatic functionality — achieved using the standard steering-wheel shift paddles — offers a welcome dose of added control.

But where this engine really scores, of course, is in its economy and exhaust emissions. According to mandated European driving cycles, the AJD-V6 helps the XF 2.7D deliver a combined fuel economy of 37.6 mpg, which compares with 26.8 mpg for the 3.0 V6 and 22.4 mpg for the X4.2 V8 S/C models.

Its carbon-dioxide emissions of 199 g/km compare with a best of 249 g/km for a gasoline XF. If you live in London, this will make a massive difference when the revised traffic congestion charge for city-center travel comes into being in October. You will be asked to pay $16 per day to drive a diesel Jaguar XF in the central zone, instead of $50 per day for a gasoline car.

The Overall Package

The XF is very much a make-or-break car for Jaguar. The retro styling of the old S-Type had quickly become dreary, and the new Ian Callum-directed look is more in keeping with modern London, which has become a showcase of contemporary design.

Like many, we've noticed that the XF's profile has independently popped up on the drawing board of a lot of designers (the Lexus GS is one example), yet the XF's bold front grille and carefully crafted detailing help this car assert its own visual identity. Whether people will instantly recognize it as a Jaguar is open to debate, but given the company's recent plight, maybe that's not such a bad thing.

The cabin is even more convincing. Neat, modern, well-built and cosseting, it makes the cockpit of an E-Class or 5 Series feel old hat. The blue mood lighting at night is particularly effective, lending the car an upmarket feel without appearing contrived. The only key criticism inside concerns the rear-seat leg- and headroom. Anyone over 6 feet tall will find it a squeeze, especially when compared with the Audi A6.

In its new incarnation, Jaguar is trying to present itself as the manufacturer of sport sedans, and the XF represents a good start. Fine damping coupled with linear steering response delivers a car that's genuinely good to drive. The compact, comparatively lightweight diesel engine also does nothing to upset its handling balance. Anyone stepping out of a BMW 5 Series will not be disappointed by the Jaguar XF 2.7D.

The Future of the Jaguar Diesel

In today's European market, Jaguar's problem is not that it offers a diesel XF, but instead that it offers only one. The 2.7-liter AJD-V6 is a thoroughly modern engine, but it means the XF's primary sales volume in the diesel market places it among smaller, less powerful cars like the BMW 520d. Meanwhile, Jaguar doesn't have a more potent diesel to compete with the BMW 535d and Mercedes-Benz E320CDi. Such is the dominance of diesel in Europe that you really need a range of engines to be a major market force.

Judged in isolation, though, the 2008 Jaguar XF 2.7D must be hailed as a success. With its blend of refinement, comfort and easygoing performance, it is very much a Jaguar and it offers the best combination of attributes in the XF range.

These are qualities that would also make it a fine car for the U.S., but Jaguar has no Bluetec-style technology to clean up the diesel's particulate emissions. If we were Tata, Jaguar's new owners from India, we'd be looking very hard at a workable diesel plan for both Jaguar and Land Rover in America.


2008 Jaguar XF 2.7D First Drive


M

Very impressive.

It looks like the 2.7 litre diesel engine is great - but they are right!! To be a real competitor to the german brands, Jaguar needs to improve their diesel engines!!

They also need a 4 pot 2L one to compete with the 520d and E220 CDI.

I can not really imagine, that there is a market for a smaller diesel engine here! They Jaguar will never be in vehicle fleets of companies I think and there will be also no Jaguar Taxis.
There are less people, who are considering to buy a Jag. When I remember, how many people were on the presentation of the XF - nearly no one, and we were the only one, who are not driving a Jag!