The Hyundai Sonata IV (EF) 2.5 V6, produced between 1998 and 2001, represented a significant step forward for the South Korean automaker in the mid-size sedan segment. Part of the EF generation (internally designated as the fourth Sonata), this variant offered a more powerful engine option compared to the base 2.0L models, aiming to attract buyers seeking a blend of comfort, space, and performance. The EF Sonata was crucial in establishing Hyundai’s reputation for value and reliability in the North American market, where it was increasingly seen as a viable alternative to established Japanese and American brands. This 2.5 V6 trim occupied the upper-mid range of the Sonata lineup, positioned below any potential limited edition or fully-loaded trims, but above the more economical 2.0L versions.
Technical Specifications
| Brand | Hyundai |
| Model | Sonata |
| Generation | Sonata IV (EF) |
| Type (Engine) | 2.5 V6 (175 Hp) |
| Start of production | 1998 |
| End of production | 2001 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel Type | Petrol (Gasoline) |
| Maximum speed | 220 km/h (136.7 mph) |
| Weight-to-power ratio | 7.7 kg/Hp, 129.6 Hp/tonne |
| Weight-to-torque ratio | 5.9 kg/Nm, 170.4 Nm/tonne |
| Power | 175 Hp @ 6000 rpm |
| Power per litre | 70.2 Hp/l |
| Torque | 230 Nm @ 4000 rpm (169.64 lb.-ft. @ 4000 rpm) |
| Engine layout | Front, Transverse |
| Engine Model/Code | Delta / G6BV |
| Engine displacement | 2494 cm3 (152.19 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 84 mm (3.31 in.) |
| Piston Stroke | 75 mm (2.95 in.) |
| Compression ratio | 10:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 4.5 l (4.76 US qt | 3.96 UK qt) |
| Kerb Weight | 1350 kg (2976.24 lbs) |
| Trunk (boot) space – minimum | 396 l (13.98 cu. ft.) |
| Fuel tank capacity | 65 l (17.17 US gal | 14.3 UK gal) |
| Length | 4710 mm (185.43 in.) |
| Width | 1818 mm (71.57 in.) |
| Height | 1410 mm (55.51 in.) |
| Wheelbase | 2700 mm (106.3 in.) |
| Front track | 1540 mm (60.63 in.) |
| Rear (Back) track | 1520 mm (59.84 in.) |
| Drag coefficient (Cd) | 0.32 |
| Minimum turning circle (turning diameter) | 10.5 m (34.45 ft.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the front wheels of the vehicle. |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 5 gears, manual transmission |
| Front suspension | Independent, type McPherson with coil spring and anti-roll bar |
| Rear suspension | Independent multi-link suspension |
| 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 | 205/60 R15 |
| Wheel rims size | 15 |
Powertrain & Engine Architecture
The heart of the Sonata IV 2.5 V6 was the Hyundai Delta engine, specifically the G6BV code. This 2.5-liter, naturally aspirated V6 engine featured a 60-degree V-angle and a dual overhead camshaft (DOHC) valvetrain with four valves per cylinder. The multi-port fuel injection system delivered fuel directly to each intake port, optimizing combustion efficiency. The engine’s 10:1 compression ratio contributed to its respectable power output. The 5-speed manual transmission was the standard offering, providing drivers with direct control over the engine’s power. The engine was designed with a focus on durability and ease of maintenance, reflecting Hyundai’s growing emphasis on build quality.
Driving Characteristics
The 2.5 V6 Sonata offered a noticeable performance upgrade over the base 2.0L models. With 175 horsepower and 169.64 lb-ft of torque, acceleration was brisk, making highway merging and overtaking maneuvers considerably easier. The 5-speed manual transmission allowed for precise gear selection, maximizing the engine’s power band. While not a sports sedan, the V6 provided a smooth and refined driving experience. The gear ratios were tuned for a balance between acceleration and fuel economy, prioritizing everyday usability over outright performance. Compared to the 2.0L, the V6 felt significantly more relaxed at highway speeds, requiring less frequent downshifting.
Equipment & Trim Levels
The 2.5 V6 Sonata typically came equipped with features such as air conditioning, power windows and locks, and an upgraded audio system. Interior upholstery was generally cloth, though leather options were available. The dashboard layout was functional and straightforward, prioritizing ease of use. Optional extras included a sunroof, alloy wheels, and a CD player. The trim level often included features like a trip computer and upgraded interior trim. The focus was on providing a comfortable and well-equipped vehicle at a competitive price point.
Chassis & Braking
The Sonata IV utilized an independent McPherson strut suspension in the front and an independent multi-link suspension in the rear, providing a comfortable ride and decent handling characteristics. Ventilated disc brakes were fitted to the front wheels, while the rear wheels featured disc brakes. An anti-lock braking system (ABS) was standard, enhancing safety. The chassis was designed to provide a stable and predictable driving experience, prioritizing comfort over sporty handling. The steering was hydraulic power-assisted, offering a light and responsive feel.
Market Reception & Comparison
The 2.5 V6 Sonata was generally well-received by automotive critics, who praised its spacious interior, comfortable ride, and strong value proposition. It was often compared favorably to competitors like the Honda Accord and Toyota Camry. While the V6 engine offered more power than the base 2.0L, fuel economy was slightly lower. However, the added performance was often considered worth the trade-off. Reliability was also a strong point, with the Delta engine proving to be durable and relatively trouble-free. The 2.0L models were favored by those prioritizing fuel efficiency, while the V6 appealed to buyers seeking more power and refinement.
Legacy
The Hyundai Sonata IV 2.5 V6 played a pivotal role in establishing Hyundai as a serious contender in the mid-size sedan market. The Delta engine proved to be a reliable and durable powerplant, and many examples are still on the road today. In the used car market, these Sonatas are often sought after for their affordability and practicality. While not a collector’s item, the EF Sonata represents a significant milestone in Hyundai’s history, demonstrating the company’s commitment to quality and innovation. The 2.5 V6 variant, in particular, is remembered for its smooth power delivery and comfortable driving experience.




