Audi RS 5 vs. Mercedes-AMG C 63 Coupé: Complete comparison 2026

The Audi RS 5, a masterpiece from Ingolstadt renowned for the unwavering confidence of its quattro all-wheel drive and its technologically advanced twin-turbocharged six-cylinder engine, represents the pinnacle of elegance combined with stunning speed and everyday usability. Facing off against it is the Mercedes-AMG C 63 Coupé (often known in its more powerful variant as the C 63 S or under its former designation, the Mercedes-Benz C 63 AMG), an iconic rear-wheel-drive car from Affalterbach that captivates automotive enthusiasts with the unmistakable roar and brutal power of its full-blooded V8. Dive into our detailed comparison and find out whether, in the battle of these exceptionally attractive used cars, the cool traction precision of the four rings or the untamed emotions and burnt rubber of the three-pointed star on the hood will prevail.

Exterior dimensions and proportions

When looking at the exterior dimensions of both iconic sports cars, we encounter some very interesting differences. Focusing on models available on the used car market around four years old (F5 generation for Audi and 205 for Mercedes), the Mercedes-AMG C 63 Coupé gives a more robust overall impression. With a length of 4,751 mm, it is 28 mm longer than the Audi RS 5 Coupé and offers a massive 74 mm longer wheelbase (2,840 mm vs. 2,766 mm). Audi, on the other hand, counters with a lower body height – it is 29 mm lower, which gives it a more crouched, aggressive stance and helps slightly lower the center of gravity. This difference in proportions directly affects the character of both cars: the more compact and lower Audi will appeal to buyers who prefer the feeling of a tight, purely sporty connection with the road, while the longer wheelbase and overall build of the Mercedes will convince drivers looking for more stable behavior at high speeds and a visually more substantial silhouette.

An interesting comparison arises with the more practical five-door and four-door variants of both rivals. The Audi RS 5 Sportback (sloping rear with a liftgate) outgrows the rival Mercedes-AMG C 63 Sedan by 26 mm in length and is also noticeably wider (1,866 mm vs. 1,839 mm). However, Mercedes maintains a shared platform and a 2,840 mm wheelbase across models, which is still 14 mm longer than the Sportback version. These parameters play a crucial role for family-oriented buyers. Audi's wider and longer body brings better practicality thanks to the huge trunk opening, but the Mercedes Sedan benefits from a higher roof and longer wheelbase, which is a clear advantage if you require maximum headroom and legroom for adult passengers in the back.

A significant factor when choosing a used car approximately four years old is the variety of body styles available. A strong weapon for the Stuttgart-based carmaker in the 205 generation is the availability of a purely family-oriented estate version (T-Modell), which extends the body to 4,772 mm and increases the overall height to achieve maximum internal volume. At Audi, those interested in a classic family estate (Avant) with the RS 5 badge will have to wait for the entirely new B10 generation from 2026. Therefore, if the decisive factor when choosing a high-performance used car is the largest possible transport capacity combined with a traditional "boxy" trunk shape, the Mercedes in the estate version becomes an unrivaled choice, against which Audi in the compared generation can only offer a stylish compromise in the form of an elegant liftback.

Although customers buy high-performance cars like Audi RS 5 and Mercedes-AMG C 63 primarily for their top-tier driving dynamics, in the role of daily drivers, trunk capacity plays a key role. Whether it's everyday family usability, sufficient space for weekend shopping, or packing for a longer vacation, the practicality of the trunk can significantly influence overall satisfaction with the vehicle. Both automakers offer completely different approaches to interior space solutions in the market for approximately four-year-old used cars (we are focusing on reliably proven vehicles from the F5 generation for Audi and the 205 generation for Mercedes), which depend primarily on your chosen body style.

In the case of the Audi RS 5, buyers have a choice between the classic two-door Coupé and the much more practical five-door Sportback model (which falls into the hatchback/liftback category by standard definitions). While the Coupé from 2020–2023 offers a base trunk volume of 410 liters, a value perfectly sufficient for the standard luggage of two passengers, the Sportback version is the true all-rounder. It boasts not only a larger base volume of 465 liters but also offers unparalleled access to the trunk thanks to its massive liftgate. After folding down the rear seats, the space increases to an impressive 1,280 liters. Such a vast loading area easily swallows sports equipment and provides ample room for several extra suitcases.

The competing Mercedes-AMG C 63 of the 205 generation counters with a wider range of body styles, but its direct competitor, the two-door Coupé, is significantly more modest in terms of space – the trunk volume here is just 355 liters. If you require more space in the "C-Class," you need to go for the four-door Sedan version, which offers a more generous 480 liters, or choose a purely family-oriented path with the station wagon version labeled T-Modell (Estate). This features a base volume of 490 liters, and after folding the backrests, the space expands to a maximum of 1,510 liters, covering even the most demanding transport tasks. Just be careful if you are considering the newer generation of the vehicle (the C 63 S E PERFORMANCE version, designated 206, sold since 2023). In this plug-in hybrid variant, a large part of the trunk had to make way for the traction battery, which is why the trunk capacity has shrunk to just 280 liters for the sedan and 360 liters for the estate.

Trunk Capacity Comparison

If practicality and towing capacity are key for you when choosing a high-performance car, the battle between the Audi RS 5 and Mercedes-AMG C 63 Coupé models has very specific rules. For typical representatives on the used car market around four years old – namely the F5 (Audi) and 205 (Mercedes) generations – do not expect any miracles in this regard. The official standard and maximum trailer weight for both of these pure-bred sports coupes is exactly 0 kg. Due to the large rear diffusers, sports exhaust systems, and ultimate focus on driving dynamics, models from this era have no factory homologation for the installation of a tow bar.

However, the situation changes radically if we look at different and newer versions. The upcoming generations of both cars bring an unexpected shift. While older models with large-displacement engines do not allow towing, the modern plug-in hybrid version Mercedes-AMG C 63 S E PERFORMANCE (generation 206) offers a respectable standard and maximum braked trailer weight of 1800 kg. It is ably seconded by the brand-new generation Audi RS 5 (B10), where the maximum and standard value has climbed to 1900 kg.

In practice, these generational differences represent a huge step forward in everyday usability. While with four-year-old used cars you must rely exclusively on the internal trunk capacity, connecting a trailer to more modern hybrid and newer models brings flexible space for several extra suitcases, representing a transport capacity more than sufficient for weekend shopping or a longer holiday with the whole family.

In conclusion, trailer weight will not make your decision between typical four-year-old used cars of both models any easier, as neither of them allows towing and tabular data for these versions does not exist. However, if towing is an absolute necessity, it makes clear sense to consider moving to newer (often plug-in hybrid) generations, which can handle this requirement surprisingly well.

Comparison of Powertrains

When choosing a high-performance coupe on the used car market (roughly four-year-old vehicles), the Audi RS 5 and Mercedes-AMG C 63 represent completely different engineering approaches, which has a fundamental impact on daily usability, efficiency, and emotions behind the wheel. While Audi bets on certainty and technological precision thanks to its twin-turbocharged 2.9 TFSI V6 paired with advanced all-wheel drive, Mercedes remains faithful to the traditional muscular concept with a hand-assembled twin-turbocharged 4.0 V8 BiTurbo, which sends its power exclusively to the rear wheels. For used car buyers, this means deciding between versatility and uncompromising character: the Audi powertrain brings excellent traction in any weather and slightly better fuel economy with higher reliability for regular commuting. Conversely, the AMG V8 stands out with brutal power, massive torque, and an unmistakable sound, making it a car sought after by demanding purists. Both manufacturers use lightning-fast multi-speed automatic transmissions that ensure flawless straight-line dynamics.

Audi RS 5: Confidence in All Weather

The Audi RS 5 (in the relevant F5 generation after the 2021–2023 facelift) does not offer different performance levels but relies on a single, perfectly tuned powertrain. Under the hood is a 2.9 TFSI V6 petrol engine with two turbochargers nestled between the cylinder banks, producing 331 kW and a massive 600 Nm of torque. Power is always and without exception distributed to all four wheels via the renowned quattro permanent all-wheel-drive system and a smooth-shifting eight-speed Tiptronic automatic transmission. The strength of this setup is rocket-like acceleration regardless of current grip and extraordinary driver-friendliness for year-round daily use. Customers focused on operating costs within this segment will also appreciate the more reasonable fuel requirements compared to larger-displacement competitors. The weakness for some may be a slightly more sterile character that cannot provide the same spectacle and acoustic drama as a bubbling V8.

Mercedes-AMG C 63 Coupé: Raw V8 Power

The engine lineup for the Mercedes-AMG C 63 Coupé (generation C205, cars from roughly 2020–2023) fulfills the dreams of traditional high-performance engine lovers. The main asset is the charismatic 4.0 V8 BiTurbo petrol engine. Unlike Audi, those interested in a late-model used car could choose from two performance specifications – the standard C 63 has 350 kW and 650 Nm, while the more powerful top-tier C 63 S AMG version jumped to a final 375 kW and a monstrous 700 Nm. All models use the nine-speed AMG SPEEDSHIFT MCT 9G dual-clutch transmission and are purely rear-wheel drive. The "S" version additionally delights sportier drivers with an electronically controlled limited-slip differential and active engine mounts. As model year data shows, the newer generation of this model (from 2024, designated as S E PERFORMANCE) has irrevocably replaced this legendary V8 with a heavy and complex four-cylinder plug-in hybrid. Since the classic pure petrol V8 engine is no longer and will not be available, C205 models with the V8 are becoming highly valued and sought-after collector's items. The weakness of this raw power is the literally murderous rate of rear tire wear and significantly higher demands for regular maintenance.

Final Recommendation

For drivers looking for a high-performance yet absolutely safe GT for year-round commuting regardless of weather and road conditions, the V6 Audi RS 5 with its legendary all-wheel drive is the clear choice. In contrast, passionate purists, enthusiasts of playful handling, and drivers looking for the unfiltered character of a traditional engine should reach for the Mercedes-AMG C 63 S Coupé without hesitation. Due to the end of pure petrol V8s in this class, the Mercedes represents not only an incredible tool for fun but also a huge perspective for value retention in the future used car market.

Choosing the right engine and drivetrain is absolutely crucial for long-term satisfaction with high-performance sports cars. In this specific league, you are not just looking for performance on paper, but the best compromise between brutal power, everyday usability, mechanical reliability, and real-world running costs. The following recommendations for roughly four-year-old used cars are based on real-world service experience, long-term owner feedback, and technical specifications. An interesting aspect of this comparison is the different approach of the manufacturers – while Audi refined its twin-turbocharged six-cylinder to absolute efficiency, Mercedes-AMG in its previous generation relied on a characterful V8, which from today's perspective represents an exceptionally prized rarity.

For the Audi RS 5, we recommend: 2.9 TFSI V6 (331 kW / 450 hp)

The core and de facto only, yet absolutely brilliant heart of the RS 5 Coupé and Sportback models (in the F5 generation, whose production for these versions ended between 2023 and 2024) is the twin-turbocharged 2.9 TFSI V6 developed in close cooperation with Porsche. This unit represents the absolute pinnacle in the ratio of everyday usability to extreme dynamics.

• Why it's the best choice: The engine has a perfectly balanced power curve with a massive 600 Nm of torque available from low revs. Combined with the lightning-fast yet smooth-shifting eight-speed Tiptronic automatic transmission and sophisticated quattro all-wheel drive, it can safely transfer power to the road in any weather. Real-world fuel consumption can be kept around a reasonable 10–11 liters per 100 km during normal travel.
• Known risks and their solutions: Mechanically, it is a very solid and reliable engine. The main downside, given the direct fuel injection and the nature of the engine, is carbon buildup on the intake valves. After exceeding roughly 80,000 km, this manifests as a rougher idle, loss of power, and poor throttle response. It can be solved by mechanical decarbonization cleaning (e.g., using walnut shells). Occasionally, issues also arise with the complex positive crankcase ventilation (PCV) system or minor coolant leaks from the plastic thermostat housings. Basic prevention includes high-quality fuel and shortening the oil change interval to a maximum of 10,000 km.
• Who it suits best: This engine is perfect for drivers looking for a year-round usable and inconspicuously fast "GT". It is the ultimate tool for safe and rocket-like long-distance travel, which, thanks to quattro, is forgiving of driver errors.

For the Mercedes-AMG C 63 Coupé, we recommend: C 63 S 4.0 V8 bi-turbo (375 kW / 510 hp)

For the Mercedes-AMG C 63 Coupé generation 205 (on sale until roughly spring 2023), it is an absolute must to look for the V8 engine with the code designation M177, ideally in the more powerful "S" variant. As available data shows, the new generation (206) has already switched exclusively to a four-cylinder plug-in hybrid under the name C 63 S E PERFORMANCE. This makes the older V8 generation W205/C205 an extremely sought-after and collectable "last of its kind" with immense charisma on the four-year-old used car market.

• Why it's the best choice: The hand-built V8 bi-turbo in the S version offers a staggering 510 hp and 700 Nm of torque, with all the power sent through a fast nine-speed MCT transmission solely to the rear wheels. This version also features an advanced electronically controlled limited-slip differential and dynamic engine mounts. The power curve and the absolutely phenomenal sound are addictive.
• Known risks and their solutions: The engine itself does not suffer from fatal defects (unlike older V8s with failing cylinder head bolts), but its servicing is financially extremely demanding. A greater risk for the M177 is the failure of the oil separator in the PCV system. If it becomes clogged, pressure forces oil through the rear crankshaft oil seal. The repair then requires removing the transmission and is very expensive. Be cautious with the transmission and differential as well – they require strict adherence to their own oil change intervals, otherwise there is a risk of rapid wear of the multi-plate clutches or a very expensive replacement of the "e-diff". The price for the brutal torque is also the extremely rapid disappearance of tread on the rear tires and brake pads.
• Who it suits best: The "S" version is intended for true purists and enthusiasts for whom driving is a passion and an experience. Compared to the clinically precise RS 5, it is a loud and hooliganistic "beast" that prefers a dynamic driving style and drifting. It is ideal for drivers who do not mind high service costs and are rewarded with true V8 character.

For sports cars with power reaching the 500 hp mark, the difference between official manufacturer data and the harsh reality on the road is often vast. Especially with roughly four-year-old used cars, whose official consumption figures were created under outdated laboratory conditions, real-world driving usually brings surprises, and paper values simply cannot be taken at face value.

To get an accurate picture of how much these powerful cars actually consume, we rely on long-term real-world data from drivers themselves, specifically from the German community portal Spritmonitor.de. We included engine versions from generations that currently make the most sense on the four-year-old used car market – namely the Audi RS 5 F5 generation (model years 2021–2023) and the Mercedes-AMG C 63 205 generation (model years 2020–2023).

Data source: Spritmonitor.de /

When interpreting real-world trends, a rather surprising finding emerges. Although Audi opted for popular downsizing with the F5 generation, replacing the previous naturally aspirated V8 with a smaller 2.9-liter twin-turbo V6, no revolutionary savings occur in practice. The difference compared to the massive four-liter V8 from AMG is actually only about one liter of fuel per hundred kilometers. This is a typical drawback of smaller turbo engines – as soon as you start using even a bit of their dynamic potential, the turbochargers must compensate for the missing displacement with a richer fuel mixture, and consumption begins to rise sharply. Naturally, we won't find any diesel engines in this league, so long "diesel-like" ranges without frequent refueling are out of the question for either rival.

For the average user, this means that if they use the car primarily for smooth highway cruising or relaxed commuting, the smaller engine in the Audi will be slightly kinder to the wallet and maintain a more reasonable appetite. However, as soon as you move into heavy city traffic with frequent starts or head out to winding backroads, both cars will cross the 15 l/100 km mark without blinking. Furthermore, in the city, the Mercedes pays the price for its huge displacement, and the bubbling V8 takes its toll for its iconic sound in the form of the fastest-disappearing tank.

In conclusion, it can be said with certainty that fuel consumption should not play any major role when deciding between these two cars. Anyone buying or financing a premium four-year-old coupe with similar performance must automatically expect high operating costs. The financial difference, which amounts to about a liter and a half of fuel, is completely negligible compared to the astronomical prices of large brake discs, wide sports tires, and comprehensive insurance. You should therefore choose the winner based on your preferred character – whether it's the surgically precise all-wheel drive from Audi or the unruly rear-wheel drive from the AMG workshops.

Used Car Market Prices: Audi RS 5 vs. Mercedes-AMG C 63 Coupé

Looking at the used car market for vehicles approximately four years old (2021–2023 models), a very different value trend emerges for both German rivals. We are comparing the Audi RS 5 B9 generation (facelift) and the Mercedes-AMG C 63 Coupé C205 generation (also facelifted). While the Audi follows a classic depreciation curve, the Mercedes benefits from strong collector potential due to the discontinuation of V8 engines.

Market Situation: Audi RS 5 (2021–2023)

Prices for used Audi RS 5 models with the 2.9 TFSI V6 biturbo engine are falling at a predictable rate typical of premium sports models. This makes it a very rational and more financially accessible choice as a used car.

• Base models: Well-maintained examples with average mileage start on the market from approximately €66,000.
• Premium equipment and mint condition: Versions with exclusive extras (such as carbon-ceramic brakes, the Competition package, or premium Bang & Olufsen audio) and low mileage climb towards the €82,000 to €91,000 mark.
• Value development: The car has a stable but natural depreciation. As a "four-year-old used car," it therefore represents an excellent price-to-performance ratio compared to the original purchase price.

Market Situation: Mercedes-AMG C 63 Coupé (2021–2023)

The situation for the "C-Class" AMG is diametrically different. The C205 generation is the last to house the legendary 4.0 V8 biturbo engine under the hood. This fact has caused the car to hold its value almost phenomenally.

• Standard C 63 (476 hp): Prices for this base engine start at approximately €62,000. Better-equipped models quickly approach the €70,000 mark.
• C 63 S version (510 hp): This significantly more desirable variant among enthusiasts ranges from €74,000 to €95,000 on the four-year-old used market. It depends primarily on optional features such as AMG Performance bucket seats or advanced braking systems.
• Value development: Extremely low depreciation. Used V8s from the final years of production are experiencing price stabilization and have real collector potential for the future.

Overview of Indicative Prices (cars approx. 4 years old)

Note: The amounts above are indicative and depend on the specific service history, mileage, and overall technical condition of the vehicle.

When evaluating the safety of used premium cars, such as four-year-old Audi RS 5 and Mercedes-AMG C 63 Coupé models, it is essential to rely on independent tests by the Euro NCAP organization. Both mentioned models achieved the maximum five-star rating in their testing cycles. However, it is crucial to view these results in the context of the time they were tested. Euro NCAP protocols and methodologies are constantly evolving and becoming stricter over the years, meaning that percentage scores from different years cannot be directly compared with the results of the latest vehicles on the market. Modern tests take much more account of advanced assistance systems, such as complex emergency scenarios at intersections or improved cyclist detection.

The Audi RS 5 B9 generation (which includes popular four-year-old used cars) structurally benefits from the A4/A5 family platform, whose crash tests took place in 2015. At the time, the car excelled with an extraordinary level of passive safety and occupant protection. The rival Mercedes-AMG C 63 Coupé, sharing its architecture with the then C-Class (C205 generation), underwent crash tests a year earlier, in 2014. It also outclassed most competitors at the time with its exceptionally robust bodywork, although the evaluation of its assistance systems logically reflects the older methodology from the beginning of the last decade.

From the perspective of today's used car market, this means that both cars offer top-tier mechanical and structural safety supported by rigid construction, sophisticated crumple zones, and a comprehensive network of airbags. However, in terms of validity under current and stricter Euro NCAP rules, their original five-star certification has already formally expired due to obsolescence. In a direct comparison of percentage results, the Audi emerged from the tests with slightly more advanced safety assistants and better protection for child passengers. The Mercedes, on the other hand, recorded slightly better results in adult occupant protection and collisions with vulnerable road users.

Ultimately, those interested in these high-performance cars need not worry at all – both provide exceptionally reliable protection in the event of an accident. However, potential buyers must take into account that the cars do not possess the absolute most advanced active systems offered by today's brand-new generations. Overall, the Audi offers a slightly more balanced and marginally more modern foundation of safety technologies, although in real-world traffic, the safety difference between the two cars is minimal.

In addition to standard equipment, each of the models offers several unique features and technological innovations that go beyond basic functionality and provide specific added value for the customer in both daily and sporty use.

Audi RS 5: Technological Precision and Unwavering Confidence

• Drive and Chassis: The cornerstone of the model is the legendary quattro permanent all-wheel drive, which can be enhanced with a sport differential on the rear axle. If the car is equipped with the Dynamic Ride Control (DRC) damping system, it uses a mechanical connection between the shock absorbers to suppress body roll, ensuring immense traction and mechanical grip in all weather conditions.
• Infotainment and Instrument Cluster: The fully digital Audi virtual cockpit plus features special "RS" display modes. These serve racing telemetry directly to the driver's eyes – from a G-meter and shift indicator to tire pressure, current torque usage, and engine oil temperature.
• Headlights and Night Visibility: The RS 5 model offers optional Matrix LED headlights equipped with laser high-beam technology. This feature not only gives the car an aggressive look thanks to blue accents in the optics but, more importantly, dramatically extends the range of the high beams in the dark and intelligently masks oncoming vehicles.
• Weight Reduction and Motorsport: For true enthusiasts, a carbon fiber roof was available. Not only does it complete the exotic exterior look, but it also saves valuable kilograms at the highest point of the car, thereby lowering the center of gravity and improving overall handling.
• Driving Assistants for Everyday Journeys: Despite its rugged character, the RS 5 offers top-tier technologies from luxury sedans, including predictive adaptive cruise control, which can independently adjust speed before intersections, curves, and speed limits based on map data.

Mercedes-AMG C 63 Coupé: Purebred Passion with Racetrack Technology

• Engine and Iconic Sound: At the heart of this model is a hand-assembled 4.0 V8 biturbo, produced according to the "One Man, One Engine" philosophy. Compared to the V6 in the Audi, it provides a completely different, much more dramatic sound experience, further enhanced by the optional AMG Performance exhaust system with electronically adjustable flaps.
• Traction and Electronic Systems: While Audi dominates with all-wheel drive, the C 63 Coupé relies solely on rear-wheel drive. The top-of-the-line C 63 S version also boasts the AMG Traction Control system derived from the AMG GT R supercar, which allows the driver to set the rear-wheel slip level in nine different stages.
• AMG Track Pace Racing Telemetry: The infotainment offers a virtual engineer function. The system can record dozens of specific data points (such as speed, acceleration, or steering angle) ten times per second. Additionally, it includes pre-loaded maps of many world racing circuits, serving as a precise track analyzer and timer.
• Smart Controls: The iconic AMG Performance steering wheel with a flat bottom is equipped with digital rotary selectors directly on the spokes. This allows the driver to lightning-fast change suspension stiffness, driving modes, or open the exhaust flaps without having to take their hands off the wheel and look for buttons on the center console.
• Comfort and Interior: The fusion of racing style with everyday comfort is demonstrated by the optional AMG Performance bucket seats with significant lateral support, whose bolsters can be pneumatically inflated to suit the body type. Furthermore, the occupants are pampered by the premium Burmester surround sound system, known for its beautifully crafted metal speaker covers.

Audi RS 5 is the perfect choice for those looking for a lightning-fast and elegant coupe for everyday use regardless of the season or weather. Thanks to quattro drive and overall soundproofing, it offers immense confidence behind the wheel, which will be especially appreciated by drivers who prefer unwavering precision over tail-happy playfulness.

The Mercedes-AMG C 63 Coupé is a genuine muscle car designed for true automotive enthusiasts who love the dramatic sound of a V8 and driving sideways. It is a much more emotive and demanding car to drive, generously rewarding sports driving enthusiasts, but in return, it requires compromises in daily comfort and winter usability.

Based on our own CarAudit inspections, long-term owner feedback, reliability statistics, and service reports, we have compiled an overview of the most common issues that used car buyers should watch out for. Given the complexity and performance of these sports models, a comprehensive vehicle inspection is always advisable before purchase to help detect costly hidden defects in time.

The Audi RS 5 B9 generation (with the 2.9 TFSI V6 engine) is an overall reliable and precisely engineered machine, yet it can experience specific faults associated with high performance and sophisticated technology.

• Engine and Cooling: The twin-turbocharged six-cylinder (engine code EA839) is relatively robust, but older models or cars with higher mileage may suffer from coolant leaks around the thermostat housing and water pump. Issues with the positive crankcase ventilation (PCV valve) system have also been recorded.
• Chassis and Suspension: The optional DRC (Dynamic Ride Control) suspension with hydraulically linked dampers is prone to pressure loss and fluid leaks. The repair itself requires specific diagnostic and service equipment and is very expensive.
• Braking System: Standard steel brakes wear out quickly under spirited driving and can warp. If the car is equipped with the optional carbon-ceramic brakes, they have extreme durability, but if mechanical damage occurs (e.g., from a flying stone), their replacement is astronomically expensive. Occasionally, they also exhibit unpleasant squealing when cold.
• Electronics and Interior: Some owners report occasional freezing of the MMI infotainment system and failures of the parking cameras. Exceptionally, plastic creaking occurs in the interior, especially around the center console or door panels.
• Transmission: The eight-speed Tiptronic automatic (torque converter from ZF) is excellent and reliable. However, to maintain its long life and smooth shifting, it is critically important to adhere to regular oil changes, which some owners neglect.

The Mercedes-AMG C 63 Coupé (C205 generation) with its iconic 4.0 V8 BiTurbo engine is considered a mechanically robust car, but its crushing performance takes an inevitable toll on consumables and stressed components.

• Engine and Exhaust System: The M177 engine is legendary for its durability, but ignition coil failures causing misfires do occur. A frequent and annoying problem is sticking or rattling flaps in the sports exhaust, a fault that often necessitates replacing the entire rear section of the exhaust system.
• Transmission: The nine-speed MCT transmission (in facelifted models; older ones have 7 speeds) occasionally suffers from jerky and clunky shifting, especially at low speeds and when downshifting to first gear. Sometimes a software update resolves this, but on cars with higher mileage, clutch pack wear may be to blame.
• Chassis and Tires: Massive torque delivered exclusively to the rear axle and aggressive rear wheel geometry mean extremely fast rear tire wear. The lifespan of a set of rear tires often does not exceed 10,000 to 15,000 kilometers. Worn active engine mounts are also a common fault.
• Interior Build Quality: Due to the very stiff and hard suspension of the C 63 version, plastics may begin to resonate and creak over time. These noises are most commonly heard from the dashboard area, the infotainment screen mount, or the center console.
• Electronics: Occasional restarts or freezing of the COMAND infotainment system and local failures of ambient lighting LED modules in the interior have been reported.

When buying a used car, a thorough inspection is key. Especially with premium sports models with exceptionally high performance, even minor maintenance neglect can mean huge future expenses. A thorough physical car inspection is an absolute necessity in this category. Here are some specific points to focus on for these two models.

When choosing an Audi RS 5:

• Chassis with DRC (Dynamic Ride Control) technology: With this popular hydraulic system, which cross-connects the shock absorbers to suppress body roll, leaks or unpleasant knocking can appear over time. During the test drive on uneven surfaces, listen carefully for bangs from the axles and visually check the shock absorber bodies for oil stains during the inspection.
• Condition of the braking system (especially for carbon-ceramics): Many second-hand RS 5 models have optional ceramic brakes. Although they usually withstand high loads and last for huge amounts of mileage, any replacement is extremely expensive. Check the discs for signs of material peeling, cracks on the edges, and focus on whether they emit excessive squealing or vibration during normal braking.
• Condition of the 8-speed Tiptronic transmission: The classic automatic from ZF is generally very robust, but with harsh treatment without regular oil changes (ideally every 60,000 km), it can start to act up. Test the smoothness of shifts under full throttle and during slow crawling in traffic – the transmission should not hesitate nonsensically or emit mechanical bangs.
• 2.9 V6 TFSI engine and coolant leaks: Pay special attention to checking the coolant level and possible leaks in the area of the water pump and thermostat housing, which is a fairly common occurrence with these six-cylinders. Also, after starting a completely cold engine, notice any unusual metallic clicking from the top of the engine, which in neglected units can indicate play in the rocker arms.

When choosing a Mercedes-AMG C 63 Coupé:

• Functionality of dynamic engine mounts (on the S version): The more powerful C 63 S variant uses active engine mounts. These can fail at higher mileages and start leaking dark fluid. If you feel unnaturally strong vibrations in the cabin during sharp acceleration, braking, or just while idling, it is very likely this costly defect.
• Behavior of the 9-speed Speedshift MCT transmission: This specific AMG transmission uses a wet start-off clutch instead of a classic torque converter. Slightly rougher or jerkier operation during morning driving with cold oil is normal, but if the transmission kicks hard or slips during normal shifting after warming up, it is a warning signal indicating a heavily worn clutch set or faulty mechatronics.
• Smoothness of the 4.0 V8 BiTurbo and condition of the coils: The engine designated M177 is a masterpiece, but under high load, it can suffer from accelerated wear of the ignition coils. This manifests as misfires and minor jerking during sharp acceleration. The engine must pull completely smoothly and without any hesitation across the entire RPM range.
• Condition of rear tires and limited-slip differential: The monstrous torque transmitted only to the rear axle takes its toll on components. If the rear tires are worn heavily asymmetrically, it indicates misaligned geometry or a past full of tire burning. In tight corners under light throttle, also listen for humming, crunching, or grinding from the rear differential.
• Sticking exhaust system flaps: The optional AMG performance exhaust has electronically controlled flaps that can start to resonate unpleasantly or get permanently stuck due to carbon deposits or corrosion. With the car stationary, try switching driving modes and verify that the exhaust sound changes immediately and no mechanical rattling is heard.

Sources: ADAC, mdcr.cz, auto.cz, autorevue.cz, chytreauto.cz, nabijecka.cz

This article was prepared using artificial intelligence tools. The section guarantor is Petr Dušek.