Drive and suspension

Four-cylinder TDI, six-cylinder TDI and four-cylinder TFSI – Audi will be offering the new A4 and A4 Avant with turbocharged engines in eight output ratings at sales launch in Europe. Their range extends from 100 kW (136 metric hp) to 180 kW (245 metric hp). All engines comply with the Euro 6d-temp emissions standard.

Five engine variants – the Audi A4 30 TDI (combined fuel consumption in l/100 km: 4.3–3.9* (54.7–60.3 US mpg); combined CO₂ emissions in g/km: 113–102* (181.9–164.2 g/mi)), the A4 35 TDI (combined fuel consumption in l/100 km: 4.2–3.8* (56.0–61.9 US mpg); combined CO₂ emissions in g/km: 110–100* (177.0–160.9 g/mi)), the A4 35 TFSI (combined fuel consumption in l/100 km: 6.0–5.5* (39.2–42.8 US mpg); combined CO₂ emissions in g/km: 138–125* (222.1–201.2 g/mi)) the A4 40 TFSI (combined fuel consumption in l/100 km: 6.1–5.8* (38.6–40.6 US mpg); combined CO₂ emissions in g/km: 138–132* (222.1–212.4 g/mi)) and the A4 45 TFSI (combined fuel consumption in l/100 km: 6.9–6.5* (34.1–36.2 US mpg); combined CO₂ emissions in g/km: 157–146* (252.7–235.0 g/mi)) – feature a mild hybrid system (MHEV) based on 12 volts, which reduces consumption while improving comfort. With the other A4 variants, this will gradually be rolled out after the market launch. This broad-based electrification makes an important contribution to reducing everyday running costs. In addition, it is helping to meet the fleet targets for consumption.

Broad-based electrification: the MHEV system

In real-world operation, the MHEV system can reduce fuel consumption by up to 0.3 liters per 100 kilometers according to Audi measurements. Its key component is a belt alternator starter (BAS) connected to the crankshaft. When the A4 decelerates due to the driver taking their foot off the accelerator, the BAS can recover up to 5 kW of power and feed it into a separate lithium-ion battery with 10 Ah capacity, which is housed in the rear of the car.

If the driver takes their foot off the accelerator between 55 and 160 km/h (34.2 and 99.4 mph), the Audi A4 can coast with the engine switched off. The start-stop range has been extended considerably. As soon as the driver accelerates again, the BAS starts the engine quickly and smoothly. From a standing start, it does this even with the brake depressed once the front camera detects that the vehicle ahead is starting to move.

Powerful and efficient: the engines of the Audi A4 models
From 100 to 140 kW: the 2.0 TDI

The four-cylinder TDI with 1,968 cc of displacement is available in three output variants. The entry-level version achieves between 1,500 and 2,750 rpm with a power output of 100 kW (136 metric hp) and 320 Nm (236.0 lb-ft) of torque. This engine propels the Audi A4 30 TDI (combined fuel consumption in l/100 km: 4.3–3.9* (54.7–60.3 US mpg); combined CO₂ emissions in g/km: 113–102* (181.9–164.2 g/mi)). The second version, at home in the A4 35 TDI (combined fuel consumption in l/100 km: 4.2–3.8* (56.0–61.9 US mpg); combined CO₂ emissions in g/km: 110–100* (177.0–160.9 g/mi)), has an output of 120 kW (163 metric hp) and produces 380 Nm (280.3 lb-ft) of torque between 1,500 and 2,750 rpm. The most powerful four-cylinder diesel in the A4, which drives the A4 40 TDI (combined fuel consumption in l/100 km: 5.3–4.9* (44.4–48.0 US mpg); combined CO₂ emissions in g/km: 140–131* (225.3–210.8 g/mi)), reaches 140 kW (190 metric hp). Between 1,750 and 3,000 rpm, it produces 400 Nm (295.0 lb-ft) of torque.

The 2.0 TDI enables powerful driving performance in all versions. The A4 30 TDI propels the Sedan from 0 to 100 km/h (62.1 mph) in 9.5 seconds and achieves a top speed of 214 km/h (133 mph). With the A4 Sedan 35 TDI, these values are 8.2 seconds and 228 km/h (141.7 mph), and 7.7 seconds and 241 km/h (149.8 mph) with the A4 Sedan 40 TDI. The NEDC values for fuel consumption and CO₂ emissions correlated from the WLTP data are 4.3–3.9 liters per 100 kilometers (54.7–60.3 US mpg) (112–102 grams of CO₂ per kilometer (180.2–164.2 g/mi)) for the A4 Sedan 30 TDI, 4.1–3.8 liters per 100 kilometers (57.4–61.9 US mpg) (109–100 grams of CO₂ per kilometer (175.4–160.9 g/mi)) for the A4 Sedan 35 TDI, and 5.3–4.9 liters per 100 kilometers (44.4–48.0 US mpg) (140–131 grams of CO₂ per kilometer (225.3–210.8 g/mi))* for the A4 Sedan 40 TDI.

The 2.0 TDI awaits with complex technical solutions – with separate coolant circuits, two balance shafts in the crankcase, a cylinder pressure sensor and substantially reduced internal friction. The versions with power outputs of 100 kW (136 metric hp) and 120 kW (163 metric hp) are part of a new evolutionary stage. Their crankcase is made from aluminum instead of gray cast iron and weighs 20 kilograms (44.1 lb) less as a result. The thermal management has been revised and the common rail injection system operates with a system pressure of 2,200 bar. The pistons are made from forged steel; the crankshaft is now 2.8 kilograms (6.2 lb) lighter.

The four-cylinder TDI engines are offered exclusively with a dual-clutch transmission that enables comfortable and highly efficient shifting.

Top-of-the-line diesel: the 3.0 TDI

At the top of the diesel range for the Audi A4 is the 3.0 TDI with 2,967 cc of displacement. It unites supreme power with cultivated refinement and efficiency. The V6, which weighs only around 200 kilograms (440.9 lb), combines a wealth of high-tech solutions – highly complex thermal management, minimized friction and a turbocharger with electrically adjustable turbine geometry.

The 3.0 TDI produces 170 kW (231 metric hp) of power and develops 500 Nm (368.8 lb-ft) of torque between 1,750 and 3,250 rpm. It propels the Audi A4 Sedan 45 TDI (combined fuel consumption in l/100 km: 5.5–5.3* (42.8–44.4 US mpg); combined CO₂ emissions in g/km: 144–139* (231.7–223.7 g/mi)) from 0 to 100 km/h (62.1 mph) in 6 seconds and takes it to a top speed of 250 km/h (155.3 mph). An even more powerful version of the V6 TDI will follow after the market launch.

From 110 to 180 kW: the 2.0 TFSI gasoline engine

The 2.0 TFSI, which draws its power from its 1,984 cc of displacement, is available in three variants for the Audi A4. In the first, which drives the Audi A4 35 TFSI (combined fuel consumption in l/100 km: 6.0–5.5* (39.2–42.8 US mpg); combined CO₂ emissions in g/km: 138–125* (222.1–201.2 g/mi)), the four-cylinder produces 110 kW (150 metric hp) of power and 270 Nm (199.1 lb-ft) of torque – the latter in the range from 1,350 to 3,900 rpm. In the Audi A4 40 TFSI (combined fuel consumption in l/100 km: 6.1–5.8* (38.6–40.6 US mpg); combined CO₂ emissions in g/km: 138–132* (222.1–212.4 g/mi)), it is 140 kW (190 metric hp) and 320 Nm (236.0 lb-ft) (from 1,450 to 4,200 rpm). In the top-of-the-range version Audi A4 45 TFSI (combined fuel consumption in l/100 km: 6.9–6.5* (34.1–36.2 US mpg); combined CO₂ emissions in g/km: 157–146* (252.7–235.0 g/mi)), the values are 180 kW (245 metric hp) and 370 Nm (272.9 lb-ft), which are available between 1,600 and 4,300 rpm.

The Audi A4 Sedan 35 TFSI accelerates from 0 to 100 km/h (62.1 mph) in 8.9 seconds and reaches a top speed of 225 km/h (139.8 mph). The Audi A4 Sedan 40 TFSI boasts acceleration from 0 to 100 km/h (62.1 mph) in 7.3 seconds and a top speed of 241 km/h (149.8 mph). The A4 Sedan 45 TFSI completes the standard sprint in only 5.8 seconds and achieves a top speed of 250 km/h (155.3 mph).

The two-liter gasoline engine exhibits many examples of technical finesse. In the versions with power outputs of 110 kW (150 metric hp) and 140 kW (190 metric hp), these include an additional intake manifold injection, which complements the FSI direct injection in part load operation and reduces particulate emissions. The Audi valvelift system (AVS) adjusts exhaust valve lift over two stages to optimize gas exchange. A compact rotary valve module for thermal management and the exhaust manifold integrated in the cylinder head both make a contribution to efficiency. A gasoline particulate filter ensures a further significant reduction in emissions.

The TFSI variants that produce 110 kW (150 metric hp) and 140 kW (190 metric hp) utilize an additional technology that makes them particularly efficient. The B-cycle combustion process with a shortened compression stroke and a long power stroke has been specially designed for part load operation, by far the most common operating mode. With a moderate style of driving, it allows drivers to experience the efficiency of a small displacement engine; while driving in a sporty style, on the other hand, they benefit from the dynamism and performance of a large engine.

* Figures depend on the tires/wheels used

Tailor-made: power transmission

Manual transmission, S tronic and tiptronic, front-wheel and quattro drive – Audi has tailor-made power transmission technology ready for every A4 engine variant. The entry-level gasoline-driven model is equipped with a six-speed manual transmission and will be available shortly after market introduction. Power transmission in all other engine variants is handled by an automatic transmission. Six of them use the seven-speed S tronic; the eight-speed tiptronic is reserved for the A4 45 TDI (combined fuel consumption in l/100 km: 5.6–5.3* (42.0–44.4 US mpg); combined CO₂ emissions in g/km: 145–139* (233.4–223.7 g/mi)) with the three-liter diesel engine. 

Both automatic transmissions are state-of-the-art. Their lower gears feature short, sporty ratios, while the upper gears are long to reduce revs and fuel consumption. The S tronic and tiptronic transmissions are integrated into the engine’s thermal management. Drivers can choose between the modes D, S and E, or shift gears manually using the selector lever or the shift paddles on the steering wheel. Their commands are transmitted to the transmission electrically – by wire.

The seven-speed S tronic impresses with its high level of efficiency. Its two multiplate clutches are arranged axially one behind the other, which reduces drag torque. A centrifugal force pendulum on the two-mass flywheel enables very low operating speeds. The dual-clutch transmission is designed for efficiency-enhancing operation with the MHEV system – for coasting, freewheeling and extended start-stop function.

In the A4 35 TFSI (combined fuel consumption in l/100 km: 6.0–5.5* (39.2–42.8 US mpg); combined CO₂ emissions in g/km: 138–125* (222.1–201.2 g/mi)), A4 40 TFSI (combined fuel consumption in l/100 km: 6.1–5.8* (38.6–40.6 US mpg); combined CO₂ emissions in g/km: 138–132* (222.1–212.4 g/mi)), A4 30 TDI (combined fuel consumption in l/100 km: 4.3–3.9* (54.7–60.3 US mpg); combined CO₂ emissions in g/km: 113–102* (181.9–164.2 g/mi)) and A4 35 TDI (combined fuel consumption in l/100 km: 4.2–3.8* (56.0–61.9 US mpg); combined CO₂ emissions in g/km: 110–100* (177.0–160.9 g/mi)), the seven-speed S tronic transmits its power to the front wheels.

In the A4 45 TFSI, the quattro drive with ultra technology is standard (combined fuel consumption in l/100 km: 6.9–6.5* (34.1–36.2 US mpg); combined CO₂ emissions in g/km: 157–146* (252.7–235.0 g/mi)). While the car is being driven with a moderate style, the system uses the efficient front-wheel drive. If all-wheel drive is required, a clutch instantly activates it, in certain situations even predictively. Optimized for efficiency, the quattro drive with ultra technology does not exhibit any perceptible differences from permanent systems in terms of traction and driving dynamics. 

The eight-speed tiptronic in the A4 45 TDI is an automatic torque converter transmission that shifts quickly and spontaneously. The layout of its gear sets and shifting elements provide for low drag torques and thus high efficiency. Thanks to an rpm-adaptive damper for attenuating vibrations, the V6 diesel can be operated comfortably even at low speeds.

The eight-speed tiptronic is connected to the quattro permanent all-wheel drive that operates on a purely mechanical level. Designed as a planetary gear, its self-locking center differential sends 60 percent of engine torque to the rear axle and 40 percent to the front during normal driving. When necessary, as much as 85 percent can be directed to the rear and up to 70 percent to the front.

Both quattro drivetrains operate in conjunction with wheel-selective torque control, a software feature of the Electronic Stabilization Control (ESC). During sporty driving, it perfects the handling by very gently braking the wheels on the inside of the curve, thus making the vehicle turn into the curve. The system also complements engine variants with front-wheel drive, although then it only acts on the front wheels.

Harmonious and balanced: the suspension

The balance of the suspension at the intersection point between sportiness and comfort is a great strength of the Audi A4. All engine variants combine great talents – from dynamic handling to a comfortable ride that already comes close to the level of the next higher vehicle class.

Five-link suspensions are used at the front and rear axles of the midsize models, and they can handle the longitudinal and lateral forces acting there separately as a result. The linkages and the subframes are made largely of aluminum. The track width of both the Sedan and the Avant measures 1,572 millimeters (5.2 ft) at the front, and 1,555 millimeters (5.1 ft) at the rear.

For engine variants with power outputs from 110 kW (150 metric hp), Audi provides dynamic steering. This uses a superposition gear to vary its ratio by up to 100 percent, depending on the car’s speed and the mode selected in the Audi drive select dynamic handling system. If necessary, it increases stability and driving safety further with lightning-fast automatic steering inputs.

Customers of the Audi A4 can choose from three alternatives to the standard version for the suspension. The sport suspension lowers the body by 23 millimeters (0.9 in). It is available separately or together with the 18-inch wheels in the S line sport package. The suspension with damper control, the second option, comes with particularly comfortable tuning despite the body being lowered by 10 millimeters (0.4 in).
It works in an energy-efficient way: Higher power is provided only if the valves are electrically closed to firm up the dampers. Alternative number three is the sport suspension with damper control, which also lowers the body by 23 millimeters (0.9 in).

The optional regulated CDC dampers (CDC = Continuous Damping Control) are managed via the electronic chassis platform. Designed as a central chassis control unit, it records a wealth of information about the setup of the car. Using this information about the driving situation, it can control the dampers with high precision and achieve a wide spectrum between dynamic handling and high ride comfort.

Just like the steering, the optional dynamic steering, the automatic transmission, the engine management system and the sport differential, the two suspension options with damper control are integrated in the Audi drive select dynamic handling system (standard from 140 kW/190 metric hp, available as an option below that). Via the MMI system, the driver can decide in which mode – comfort, auto, dynamic, efficiency and individual – these modules should operate. The efficiency mode is available only for engines with more than 300 Nm (221.3 lb-ft) of torque, while the MMI plus is a prerequisite for the individual profile.

Many of the wheels for the Audi A4 and A4 Avant are new to the range. In the German market, both models come with 16- or 17-inch alloy wheels as standard depending on the equipment line and engine variant. The S line exterior already features 18-inch wheels. Audi and Audi Sport offer a choice of wheels up to 19 inches in size. As standard, the 18-inch wheels are fitted with tires that exhibit particularly low rolling resistance and therefore further increase efficiency.

A wide range of brakes is also used. Up to the A4 35 TDI (combined fuel consumption in l/100 km: 4.2–3.8* (56.0–61.9 US mpg); combined CO₂ emissions in g/km: 110–100* (177.0–160.9 g/mi)) and the A4 40 TFSI (combined fuel consumption in l/100 km: 6.1–5.8* (38.6–40.6 US mpg); combined CO₂ emissions in g/km: 138–132* (222.1–212.4 g/mi)), 16-inch floating caliper brakes are fitted on the front axle. Models with the top-of-the-range engines are stopped by particularly lightweight, 17‑inch aluminum fixed caliper brakes. The internally ventilated brake discs on the front axle measure up to 338 millimeters (13.3 in) in diameter. On request, Audi supplies the calipers with a red paint finish.

*Fuel consumption and CO₂ emission figures given in ranges depend on the tires/wheels used.

All terms marked in the text are explained in detail in the technology lexicon at wheel-selective torque control.

The equipment, data and prices specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.