The Audi A4 (B6) 2.5 TDI V6 with the Multitronic transmission represents a specific configuration within the broader B6 A4 range, produced primarily during the 2001 and 2002 model years. This variant aimed to offer a blend of performance and efficiency, appealing to buyers seeking a more refined driving experience than the base models, but without the higher price tag of the flagship trims like the 3.0 V6. Positioned as a mid-range offering, it slotted between the 1.8T petrol engines and the more powerful, but also more expensive, 3.0-liter V6. The B6 generation A4, built on the Volkswagen Group’s 1HX0/A3 platform, was a significant step forward for Audi, introducing a more modern design and improved technology compared to its predecessor.
Technical Specifications
| Brand | Audi |
| Model | A4 |
| Generation | A4 (B6 8E) |
| Type (Engine) | 2.5 TDI V6 (155 Hp) Multitronic |
| Start of production | 2001 |
| End of production | 2002 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 9 l/100 km (26.1 US mpg, 31.4 UK mpg, 11.1 km/l) |
| Fuel consumption (extra urban) | 5.5 l/100 km (42.8 US mpg, 51.4 UK mpg, 18.2 km/l) |
| Fuel consumption (combined) | 6.8 l/100 km (34.6 US mpg, 41.5 UK mpg, 14.7 km/l) |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 9.4 sec |
| Acceleration 0 – 62 mph | 9.4 sec |
| Acceleration 0 – 60 mph | 8.9 sec |
| Maximum speed | 214 km/h (132.97 mph) |
| Weight-to-power ratio | 9.9 kg/Hp, 101 Hp/tonne |
| Weight-to-torque ratio | 5 kg/Nm, 202 Nm/tonne |
| Power | 155 Hp @ 4000 rpm |
| Power per litre | 62.1 Hp/l |
| Torque | 310 Nm @ 1400-3500 rpm (228.64 lb.-ft. @ 1400-3500 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | AYM |
| Engine displacement | 2496 cm3 (152.32 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 78.3 mm (3.08 in.) |
| Piston Stroke | 86.4 mm (3.4 in.) |
| Compression ratio | 18.5:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Direct injection |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 5.5 l (5.81 US qt | 4.84 UK qt) |
| Coolant | 12 l (12.68 US qt | 10.56 UK qt) |
| Kerb Weight | 1535 kg (3384.1 lbs.) |
| Max. weight | 2085 kg (4596.64 lbs.) |
| Max load | 550 kg (1212.54 lbs.) |
| Trunk (boot) space – minimum | 445 l (15.72 cu. ft.) |
| Trunk (boot) space – maximum | 720 l (25.43 cu. ft.) |
| Fuel tank capacity | 70 l (18.49 US gal | 15.4 UK gal) |
| Length | 4548 mm (179.06 in.) |
| Width | 1772 mm (69.76 in.) |
| Height | 1428 mm (56.22 in.) |
| Wheelbase | 2650 mm (104.33 in.) |
| Front track | 1528 mm (60.16 in.) |
| Rear (Back) track | 1526 mm (60.08 in.) |
| Drag coefficient (Cd) | 0.31 |
| Minimum turning circle | 11.1 m (36.42 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 | automatic transmission Multitronic |
| Front suspension | Independent multi-link suspension |
| 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 | 205/55 R16 |
| Wheel rims size | 7J x 16 |
Powertrain & Engine Architecture
The heart of this A4 variant is the 2.5-liter V6 TDI engine, designated with the code AYM. This engine is a turbocharged diesel, employing direct injection technology to maximize efficiency and power output. The direct injection system, utilizing common rail technology, precisely meters fuel directly into the combustion chamber, resulting in cleaner combustion and improved performance. The engine features a double overhead camshaft (DOHC) valvetrain, operating four valves per cylinder, optimizing airflow for increased power. The turbocharger, coupled with an intercooler, forces more air into the engine, further boosting power and torque. The Multitronic transmission, a continuously variable transmission (CVT), was a key feature. Unlike traditional automatic transmissions with fixed gear ratios, the Multitronic uses a chain and pulley system to provide a virtually infinite number of gear ratios, optimizing engine efficiency and providing smooth acceleration.
Driving Characteristics
The 2.5 TDI V6 with the Multitronic offered a distinctly different driving experience compared to the 1.8T or the manual versions of the same engine. While not as overtly sporty as the manual, the Multitronic provided smooth, seamless acceleration. The CVT’s ability to keep the engine in its optimal power band resulted in strong mid-range torque, making it well-suited for highway cruising and overtaking. However, some drivers found the CVT’s lack of distinct gear changes to feel somewhat disconnected. The 9.4-second 0-60 mph acceleration was respectable for its time, but noticeably slower than the manual transmission equipped models. The engine’s 310 Nm (228.64 lb-ft) of torque, available from 1400-3500 rpm, provided ample pulling power, making it a comfortable and capable daily driver.
Equipment & Trim Levels
The 2.5 TDI V6 Multitronic typically came with a fairly comprehensive standard equipment list. This included features like automatic climate control, power windows and mirrors, central locking, and an upgraded audio system. Interior upholstery was generally cloth, although leather options were available as an upgrade. Alloy wheels were standard, typically in a 16-inch size. Optional extras included a sunroof, navigation system, heated seats, and parking sensors. The trim level often dictated the availability of certain features, with higher trims offering more luxurious appointments and advanced technology.
Chassis & Braking
The B6 A4 featured an independent multi-link suspension system at both the front and rear, providing a comfortable ride and good handling characteristics. The 2.5 TDI V6 models typically had slightly stiffer suspension components compared to the base models to cope with the added weight of the engine. Braking was handled by ventilated discs at the front and solid discs at the rear, with ABS (Anti-lock Braking System) as standard. The hydraulic power steering provided precise and responsive steering feel.
Market Reception & Comparison
The Audi A4 2.5 TDI V6 Multitronic was generally well-received by automotive critics. It was praised for its refined engine, smooth transmission, and comfortable ride. However, some critics noted the CVT’s lack of engagement and the slightly higher price compared to the 1.8T models. Fuel economy was a strong point, with combined figures around 34.6 US mpg. Compared to the 1.8T, the 2.5 TDI offered significantly more torque and a more relaxed driving experience, but at the cost of some fuel efficiency and performance. The 3.0 V6 offered even more power, but came with a substantial price premium.
Legacy
The AYM engine, while generally reliable, is known to have some potential issues, including turbocharger failure and injector problems. The Multitronic transmission, while innovative, can be prone to issues if not properly maintained, particularly regarding fluid changes. Today, the A4 B6 2.5 TDI V6 Multitronic represents an affordable entry point into the Audi brand for enthusiasts. Well-maintained examples are becoming increasingly rare, and are sought after by those who appreciate the unique combination of diesel power, smooth transmission, and Audi refinement. Regular maintenance and preventative repairs are crucial to keeping these vehicles on the road.
