The Opel Omega B 2.5i V6 Automatic, produced between April 1994 and July 1999, represented a mid-range offering within the second generation (Omega B) of Opel’s flagship sedan. Positioned above the four-cylinder models and below the more powerful 3.0L V6, this variant aimed to provide a balance of performance, comfort, and refinement for buyers seeking a spacious and well-equipped executive car. The Omega B, built on the GM E-platform (internally designated as the 1HX0/A3 platform), was a significant step forward for Opel, offering improved build quality, technology, and a more sophisticated driving experience compared to its predecessor.
Powertrain & Engine Architecture
At the heart of the Omega B 2.5i V6 Automatic lies the X25XE engine, a 2.5-liter naturally aspirated V6. This engine is a 60-degree V-engine, utilizing an aluminum alloy cylinder head and iron block construction. It boasts a displacement of 2498 cm³ (152.44 cubic inches) and features a bore of 81.6 mm (3.21 inches) and a stroke of 79.6 mm (3.13 inches). The X25XE employs a compression ratio of 10.8:1 and a dual overhead camshaft (DOHC) valvetrain with four valves per cylinder. Fuel delivery is managed by a multi-port manifold fuel injection system, providing precise fuel metering for optimal combustion.
The engine produces a maximum power output of 170 hp (127 kW) at 5800 rpm and a peak torque of 226 Nm (166.69 lb-ft) at 3200 rpm. This power is delivered to the rear wheels via a four-speed automatic transmission. While not a particularly modern transmission by today’s standards, it was a reliable unit offering smooth shifts and adequate performance for the intended market. The transmission’s gear ratios were tuned for comfortable cruising and reasonable acceleration, prioritizing refinement over outright sportiness.
Engine Code Specifics
The X25XE engine code is crucial for identifying this specific variant. It signifies a particular iteration of the 2.5L V6, with specific calibrations for fuel injection and ignition timing. The engine oil capacity is 5.75 liters (6.08 US quarts / 5.06 UK quarts), and the coolant capacity is 9.7 liters (10.25 US quarts / 8.53 UK quarts). Proper maintenance, including regular oil and coolant changes, is essential for the longevity of this engine.
Driving Characteristics
The Omega B 2.5i V6 Automatic offered a comfortable and refined driving experience. Acceleration from 0-100 km/h (0-62 mph) took approximately 10.5 seconds, while 0-60 mph was achieved in around 10 seconds. Top speed was rated at 223 km/h (138.57 mph). Compared to the manual transmission versions of the same engine, the automatic resulted in a slight performance decrease due to the inherent power losses within the torque converter and transmission. However, the convenience and smoothness of the automatic transmission were highly valued by many buyers.
The power delivery was linear and predictable, making the car easy to drive in various conditions. The automatic transmission’s shift points were generally well-chosen, providing adequate power for overtaking and highway cruising. While not a sports sedan, the Omega B 2.5i V6 Automatic offered sufficient performance for most drivers, particularly those prioritizing comfort and refinement over outright speed.
Equipment & Trim Levels
The Omega B 2.5i V6 Automatic typically came equipped with a generous level of standard features. These included power windows, power door locks, central locking, air conditioning, and an upgraded audio system. Interior upholstery was typically cloth, although leather options were available as upgrades. The dashboard layout was functional and well-designed, with clear instrumentation and intuitive controls. Optional extras included a sunroof, heated seats, automatic climate control, and upgraded alloy wheels.
Trim levels varied depending on the market, but generally, the 2.5i V6 Automatic sat in the mid-range of the Omega B lineup. It offered a step up in terms of features and performance compared to the base models, while remaining more affordable than the top-of-the-line 3.0L V6 variants.
Chassis & Braking
The Omega B 2.5i V6 Automatic featured a robust chassis and suspension system designed for comfort and stability. The front suspension utilized coil springs, while the rear suspension also employed coil springs. The car’s kerb weight of 1605 kg (3538.42 lbs) contributed to its planted feel on the road. Braking duties were handled by ventilated discs at the front and solid discs at the rear. An Anti-lock Braking System (ABS) was standard, enhancing safety and control during emergency braking situations.
The steering system was a worm-reduction unit with hydraulic power steering, providing a comfortable and responsive steering feel. Tire size was typically 205/65 R15, mounted on 6.5J x 15 inch wheel rims. The ride height (ground clearance) was 140 mm (5.51 inches).
Market Reception & Comparison
The Opel Omega B 2.5i V6 Automatic received generally positive reviews from automotive critics. It was praised for its spacious interior, comfortable ride, and refined engine. However, some critics noted that the automatic transmission could feel slightly sluggish compared to the manual versions. Fuel economy was reasonable for a car of its size and engine displacement, but not exceptional. Compared to other trims in the Omega B lineup, the 2.5i V6 Automatic offered a good balance of performance and value. The 2.0L four-cylinder models were more fuel-efficient but lacked the power and refinement of the V6. The 3.0L V6 offered more performance but came at a higher price point.
In terms of reliability, the X25XE engine proved to be generally durable, although regular maintenance was crucial. The automatic transmission was also relatively reliable, but like any automatic, it required periodic fluid changes to ensure smooth operation.
Technical Specifications
| Brand | Opel |
| Model | Omega |
| Generation | Omega B |
| Type (Engine) | 2.5i V6 (170 Hp) Automatic |
| Start of production | April, 1994 |
| End of production | July, 1999 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 10.5 sec |
| Acceleration 0 – 62 mph | 10.5 sec |
| Acceleration 0 – 60 mph | 10 sec |
| Maximum speed | 223 km/h (138.57 mph) |
| Weight-to-power ratio | 9.4 kg/Hp, 105.9 Hp/tonne |
| Weight-to-torque ratio | 7.1 kg/Nm, 140.8 Nm/tonne |
| Power | 170 Hp @ 5800 rpm |
| Power per litre | 68.1 Hp/l |
| Torque | 226 Nm @ 3200 rpm (166.69 lb.-ft. @ 3200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | X25XE |
| Engine displacement | 2498 cm3 (152.44 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 81.6 mm (3.21 in.) |
| Piston Stroke | 79.6 mm (3.13 in.) |
| Compression ratio | 10.8:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 5.75 l (6.08 US qt | 5.06 UK qt) |
| Coolant | 9.7 l (10.25 US qt | 8.53 UK qt) |
| Kerb Weight | 1605 kg (3538.42 lbs) |
| Max. weight | 2170 kg (4784.03 lbs) |
| Max load | 565 kg (1245.61 lbs) |
| Trunk (boot) space – minimum | 530 l (18.72 cu. ft.) |
| Trunk (boot) space – maximum | 830 l (29.31 cu. ft.) |
| Fuel tank capacity | 75 l (19.81 US gal | 16.5 UK gal) |
| Length | 4785 mm (188.39 in.) |
| Width | 1785 mm (70.28 in.) |
| Height | 1450 mm (57.09 in.) |
| Wheelbase | 2730 mm (107.48 in.) |
| Front track | 1515 mm (59.65 in.) |
| Rear (Back) track | 1530 mm (60.24 in.) |
| Ride height (ground clearance) | 140 mm (5.51 in.) |
| Drag coefficient (Cd) | 0.28 |
| 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 | 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 | Worm-reduction unit |
| Power steering | Hydraulic Steering |
| Tires size | 205/65 R15 |
| Wheel rims size | 6.5J x 15 |
Legacy
The Opel Omega B 2.5i V6 Automatic, while no longer in production, remains a popular choice among enthusiasts and classic car collectors. The X25XE engine is known for its durability and relatively straightforward maintenance. In the used car market, these Omegas are often available at affordable prices, making them an attractive option for those seeking a spacious and comfortable sedan with a touch of classic European style. However, potential buyers should be aware of the age-related issues common to older vehicles, such as corrosion and wear and tear on rubber components. With proper care and maintenance, the Omega B 2.5i V6 Automatic can provide many years of reliable service.
