The Mitsubishi Diamante II 3.5 i V6 24V, produced from 1996 to 2005, represented Mitsubishi’s flagship sedan during that period. Positioned as a competitor to the Toyota Avalon, Honda Accord, and Mazda 929, the Diamante aimed to offer a blend of luxury, performance, and technology. This second generation, internally designated as the F30A series, built upon the success of the original Diamante, offering a more refined driving experience and a more powerful engine option with the 3.5-liter V6. In the North American market, it was often seen as an alternative to more established luxury brands, offering a significant amount of features for the price.
Technical Specifications
| Brand | Mitsubishi |
| Model | Diamante |
| Generation | Diamante II |
| Type (Engine) | 3.5 i V6 24V (208 Hp) |
| Start of production | 1996 |
| End of production | 2005 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 14 l/100 km (16.8 US mpg) |
| Fuel consumption (extra urban) | 9 l/100 km (26.1 US mpg) |
| Fuel Type | Petrol (Gasoline) |
| Maximum speed | 210 km/h (130.49 mph) |
| Weight-to-power ratio | 7.5 kg/Hp |
| Weight-to-torque ratio | 5.2 kg/Nm |
| Power | 208 Hp @ 5000 rpm |
| Power per litre | 59.5 Hp/l |
| Torque | 300 Nm @ 3000 rpm (221.27 lb.-ft. @ 3000 rpm) |
| Engine layout | Front, Longitudinal |
| Engine displacement | 3497 cm3 (213.4 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 93 mm (3.66 in.) |
| Piston Stroke | 85.8 mm (3.38 in.) |
| Compression ratio | 9.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Kerb Weight | 1550 kg (3417.17 lbs.) |
| Trunk (boot) space (minimum) | 418 l (14.76 cu. ft.) |
| Fuel tank capacity | 72 l (19.02 US gal | 15.84 UK gal) |
| Length | 4805 mm (189.17 in.) |
| Width | 1785 mm (70.28 in.) |
| Height | 1440 mm (56.69 in.) |
| Wheelbase | 2720 mm (107.09 in.) |
| Front track | 1545 mm (60.83 in.) |
| Rear track | 1535 mm (60.43 in.) |
| Drivetrain Architecture | Front wheel drive |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 4 gears, automatic transmission |
| Front suspension | Coil spring |
| Rear suspension | Coil spring |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | 205/65 R15 |
Powertrain & Engine Architecture
The heart of the Diamante II 3.5 i V6 was the 6A13 engine, a 3.5-liter, 24-valve V6. This engine featured a 90-degree V-angle, contributing to a smoother power delivery. The engine utilized a multi-port fuel injection system, delivering fuel directly to each cylinder for optimized combustion. The double overhead camshaft (DOHC) valvetrain, with four valves per cylinder, further enhanced breathing and high-rpm performance. The 4-speed automatic transmission, while not the most modern by today’s standards, was chosen for its smoothness and reliability. It was designed to provide comfortable shifts, prioritizing a relaxed driving experience over outright performance. The transmission featured electronically controlled torque converter lock-up for improved fuel efficiency at highway speeds.
Driving Characteristics
The Diamante II 3.5 i V6 offered a comfortable and refined driving experience. The 208 horsepower and 221 lb-ft of torque provided adequate acceleration, though it wasn’t a particularly sporty vehicle. The automatic transmission, while smooth, did result in some power loss compared to the available 5-speed manual transmission found in some markets. The gear ratios were tuned for cruising, making it a pleasant highway companion. Compared to the lower-displacement 2.5-liter V6 option, the 3.5-liter engine offered a noticeable improvement in both acceleration and overall responsiveness. However, it came at the cost of slightly increased fuel consumption.
Equipment & Trim Levels
The Diamante II 3.5 i V6 typically came well-equipped, reflecting its positioning as a near-luxury vehicle. Standard features often included leather upholstery, power-adjustable front seats, a premium sound system, automatic climate control, and power windows and locks. Higher trim levels added features like a sunroof, upgraded audio systems, and woodgrain interior trim. Optional extras included a navigation system (a relatively new feature at the time), and upgraded alloy wheels. The interior design focused on comfort and spaciousness, with a relatively simple and intuitive layout.
Chassis & Braking
The Diamante II utilized a front-engine, front-wheel-drive layout. The suspension consisted of coil springs all around, providing a comfortable ride. The front suspension incorporated MacPherson struts, while the rear utilized a multi-link setup. Braking duties were handled by ventilated discs at the front and solid discs at the rear. Anti-lock braking system (ABS) was standard, enhancing safety. The steering was a rack-and-pinion system with hydraulic power assistance, providing a light and responsive feel. The tires were typically 205/65R15, balancing ride comfort and handling.
Market Reception & Comparison
The Diamante II 3.5 i V6 received generally positive reviews from automotive critics. It was praised for its comfortable ride, spacious interior, and generous features list. However, some critics noted that its styling was somewhat conservative and that its handling wasn’t as sharp as some of its European competitors. Fuel economy was also a point of concern, particularly in urban driving. Compared to the 2.5-liter V6 version, the 3.5-liter offered significantly more power but at a higher price point and with slightly lower fuel efficiency. The 3.5L was aimed at buyers who prioritized performance and refinement over fuel economy.
Legacy
The Mitsubishi Diamante II, while not a massive sales success, remains a fondly remembered vehicle for those who owned one. The 6A13 engine, in particular, is known for its durability and reliability, provided it was properly maintained. Today, well-maintained examples are becoming increasingly rare and are sought after by enthusiasts. While the 4-speed automatic transmission is showing its age, it remains relatively reliable. The Diamante II represents a period when Mitsubishi was attempting to establish itself as a serious player in the luxury sedan market, and the 3.5 i V6 variant was the pinnacle of that effort.
