The Jaguar XJ Long (X351) 3.0d V6, produced from 2009 to 2012, represented a significant evolution in Jaguar’s flagship sedan. Positioned as a premium offering within the XJ range, this variant combined the extended wheelbase of the ‘Long’ body style with a potent 3.0-liter turbocharged diesel V6 engine paired to a six-speed automatic transmission. It aimed to deliver a blend of luxury, performance, and improved fuel efficiency, appealing to buyers seeking a sophisticated grand tourer. The X351 generation marked a departure from the traditional Jaguar aesthetic, embracing a more modern and streamlined design language. This model played a crucial role in Jaguar’s attempt to compete more effectively with established German rivals like the BMW 7 Series and Mercedes-Benz S-Class.
Technical Specifications
| Brand | Jaguar |
| Model | XJ |
| Generation | XJ Long (X351) |
| Type (Engine) | 3.0d V6 (275 Hp) Automatic 6-speed |
| Start of production | 2009 |
| End of production | 2012 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – urban (NEDC) | 9.7 l/100 km (24.2 US mpg, 29.1 UK mpg, 10.3 km/l) |
| Fuel consumption (economy) – extra urban (NEDC) | 5.8 l/100 km (40.6 US mpg, 48.7 UK mpg, 17.2 km/l) |
| Fuel consumption (economy) – combined (NEDC) | 7.2 l/100 km (32.7 US mpg, 39.2 UK mpg, 13.9 km/l) |
| CO2 emissions (NEDC) | 189 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 6.4 sec |
| Acceleration 0 – 62 mph | 6.4 sec |
| Acceleration 0 – 60 mph | 6 sec |
| Maximum speed | 250 km/h (155.34 mph), Electronically limited |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 6.6 kg/Hp, 151.7 Hp/tonne |
| Weight-to-torque ratio | 3 kg/Nm, 330.9 Nm/tonne |
| Power | 275 Hp @ 4000 rpm |
| Power per litre | 91.9 Hp/l |
| Torque | 600 Nm @ 2000 rpm (442.54 lb.-ft. @ 2000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | 306DT |
| Engine displacement | 2993 cm3 (182.64 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 90 mm (3.54 in.) |
| Compression ratio | 16:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | BiTurbo, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 6.6 l (6.97 US qt | 5.81 UK qt) |
| Coolant | 12.3 l (13 US qt | 10.82 UK qt) |
| Kerb Weight | 1813 kg (3996.98 lbs.) |
| Max. weight | 2365 kg (5213.93 lbs.) |
| Max load | 552 kg (1216.95 lbs.) |
| Trunk (boot) space – minimum | 520 l (18.36 cu. ft.) |
| Fuel tank capacity | 82 l (21.66 US gal | 18.04 UK gal) |
| Length | 5247 mm (206.57 in.) |
| Width | 1894 mm (74.57 in.) |
| Width with mirrors folded | 1950 mm (76.77 in.) |
| Width including mirrors | 2105 mm (82.87 in.) |
| Height | 1457 mm (57.36 in.) |
| Wheelbase | 3157 mm (124.29 in.) |
| Front track | 1626 mm (64.02 in.) |
| Rear (Back) track | 1604 mm (63.15 in.) |
| Minimum turning circle (turning diameter) | 12.3 m (40.35 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 6 gears, automatic transmission |
| Front suspension | Coil spring, Double wishbone, Transverse stabilizer |
| Rear suspension | Independent multi-link suspension, Air suspension, Transverse stabilizer |
| Front brakes | Ventilated discs |
| Rear brakes | Ventilated discs |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | Front wheel tires: 245/50 R18; 245/45 R19 Rear wheel tires: 275/45 R18; 275/40 R19 |
| Wheel rims size | Front wheel rims: 8J x 18; 9J x 19 Rear wheel rims: 9J x 18; 10J x 19 |
Powertrain & Engine Architecture
The heart of the XJ Long 3.0d was Jaguar’s 306DT engine, a 2,993cc (182.64 cu. in.) V6 diesel. This engine utilized a sequential twin-turbocharger system with a variable geometry turbine (VGT) to deliver both strong low-end torque and high-end power. The engine employed a common rail direct injection system, operating at a high compression ratio of 16:1. The DOHC valvetrain, with four valves per cylinder, further enhanced breathing and efficiency. The six-speed automatic transmission, sourced from ZF, was a crucial component, offering smooth shifts and contributing to the car’s refined driving experience. The transmission was programmed to prioritize comfort and fuel economy, with a focus on seamless gear changes rather than aggressive downshifts.
Driving Characteristics
The 3.0d V6 Automatic offered a distinctly different driving experience compared to the higher-performance XJ variants, such as those equipped with the supercharged V8 engines. While not as overtly sporty, the 3.0d provided ample power for effortless cruising and confident overtaking. The 60 mph sprint took around 6 seconds, and the electronically limited top speed of 155 mph was more than sufficient for most drivers. The automatic transmission, while smooth, could feel slightly hesitant during quick acceleration, particularly when compared to the responsiveness of a manual gearbox. The long wheelbase of the XJ Long contributed to a comfortable and stable ride, absorbing bumps and imperfections in the road with ease. The emphasis was on providing a relaxed and refined grand touring experience.
Equipment & Trim Levels
The XJ Long 3.0d typically came well-equipped as standard. Interior appointments included leather upholstery, wood veneer trim, and a premium audio system. Standard features also included automatic climate control, power-adjustable seats with memory function, and a navigation system. Optional extras included a rear seat entertainment system, upgraded leather options, and various driver assistance technologies. The ‘Long’ wheelbase provided significantly more rear legroom than the standard XJ, making it particularly appealing to chauffeur-driven buyers. Trim levels varied depending on the market, but generally offered increasing levels of luxury and technology.
Chassis & Braking
The XJ Long 3.0d utilized an aluminum monocoque chassis, contributing to its relatively low weight for a large luxury sedan. The front suspension featured a double wishbone setup with coil springs and a transverse stabilizer bar, while the rear suspension employed an independent multi-link system with air suspension and a transverse stabilizer bar. The air suspension provided adjustable ride height and further enhanced ride comfort. Braking duties were handled by ventilated discs on all four wheels, coupled with an anti-lock braking system (ABS) for enhanced safety. The braking system was generally considered effective, providing ample stopping power.
Market Reception & Comparison
The XJ Long 3.0d was generally well-received by automotive critics. It was praised for its comfortable ride, refined interior, and fuel efficiency. The diesel engine was considered a good match for the XJ’s grand touring character, providing ample power without sacrificing economy. Compared to the V8-powered XJ variants, the 3.0d offered a more affordable entry point into the XJ range, while still delivering a luxurious experience. However, some critics noted that the automatic transmission could feel slightly sluggish at times, and that the diesel engine lacked the aural excitement of the V8. Fuel economy figures of around 32.7 US mpg combined were competitive for its class.
Legacy
The Jaguar XJ Long 3.0d V6 (X351) has proven to be a relatively reliable vehicle in the used car market. The 306DT engine, while complex, is generally considered durable when properly maintained. Common issues include problems with the air suspension system and occasional issues with the electronic systems. However, these are typically addressable with proper maintenance and repair. Today, the XJ Long 3.0d represents a compelling value proposition for buyers seeking a luxurious and comfortable grand tourer at a reasonable price. Its blend of performance, efficiency, and refinement continues to appeal to enthusiasts and discerning drivers alike.
