A Bland Bargain Luxury Sports Sedan That Packs A Monster V-10 Heart

Summary

• The Audi S6 blends performance with luxury, packing a V-10 engine similar to a Lamborghini Gallardo, all in an unassuming package.
• Unlike its loud exhaust rivals, the S6 prioritizes luxury and class, being a wolf in sheep’s clothing with impressive V-10 power.
• The S6’s V-10 engine provides an unmatched driving thrill, but be prepared for poor gas mileage and potential maintenance issues over time.

The Audi S6 is one of the biggest and greatest vehicles to come out of Audi’s acquisition of Lamborghini. Combining an Italian supercar heart with German luxury results in a vehicle that blends performance with luxury and opulence in an unassuming package. The C6 generation Audi S6 is a humbling reminder that some vehicles on the road can hold their own against sports cars given the right encouragement. And since the S6 makes use of the Audi A6 platform, its unassuming design makes it a wolf in sheep’s clothing.

While the Mercedes-Benz E63 AMG and BMW M5 of the same era made getting noticed a priority with loud exhaust and slapping-on performance badging on every corner, the Audi S6 flew under the radar as its core aim was to make a statement of luxury and class even though it packed a killer 5.2-liter V-10 engine under the hood that was near identical to the units found in the V-10-powered Lamborghini Gallardo at the time.

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UPDATE: 2024/02/27 BY MARNUS MOOLMAN

Most car enthusiasts love cars that look like everyday traffic but have the performance figures of a sports car. These fast unassuming cars, better known as sleeper cars typically share an engine with a much more expensive or sought-after exotic car. Such is exactly the case with the Lamborghini-powered C6-generation Audi S6.

Here is an updated version of everything you need to know about one of the best-used car buys for 2024.

We’ve looked up data from Audi, RepairPal, Fueleconomy.gov, and classic.com to put this feature together on the C6 Audi S6.

Audi S6: Started From Humble Beginnings

The Audi S6 rose from its humble beginning as a sportier version of the brand’s A6 sedan that also replaced the outgoing Audi 100 in the late 1990s. Since then Audi has stuck to their process of creating the S6 sedan by taking a basic A6 and improving engine performance, suspension, and technology, and adding luxurious amenities. This process of making an S6 is still evident in the brand’s sport-oriented sedans to this day, what makes the C6 generation S6 unique is it remains the only generation vehicle to be powered by a V-10 engine.

A departure from this characteristic occurred in the fourth-generation C7 Audi S6, where the V-10 engine gave way to a 4.0-liter bi-turbo V-8 powerplant, which produces an impressive 414 horsepower and 406 pound-feet of torque. Audi took this a step even further with the Audi RS6 Avant which squeezes more than 600 horsepower from its twin-turbo V-8 engine. While undeniably potent, the V-8 engine fails to replicate the exotic sound evoked by the mighty V-10 engine of the C6 generation, even with the assistance of twin turbos.

A Tamed Heart: Audi’s V-10 Engine

The Audi S6’s V-10 engine is often referred to as a Lamborghini engine or as two straight-five engines found in numerous Audi models stuck next to each other. Unfortunately, this blanket statement is technically incorrect. Where the two vehicles’ engines remained unchanged is in the core architecture, both were aluminum alloy V-10 engines. The Audi S6 had a displacement of 317 cubic inches or 5.2 liters whereas the Lamborghini displaced 305 cubic inches or 5.0 liters.

The engineers at Audi increased the displacement of the S6’s V-10 to tame the sporty characteristic the engine would normally display in the Gallardo or its successor, the Lamborghini Huracan. The increased displacement improved the low-end torque performance needed to move the massive 4,486-pound sedan. The final result of the tweaks is an engine that produces 429 horsepower and 398 pound-feet of torque that went to all four wheels via Audi’s Quattro symmetrical all-wheel drive system. You could take control of the ZF six-speed automatic transmission with the available paddle shifters.

2008 Audi S6 Engine Specification

(Source: Audi)

Whether you’re unleashing its power on the open road or navigating through tight corners, the V-10 engine in the Audi S6 provides an unmatched driving thrill. The thrill of driving the S6 comes at a hefty cost as the V-10 engine is horrendous on gas mileage, rated at 14 mpg in the city, 19 mpg on the highway, and 16 mpg combined.

It’s reasons like these why more people by the day buy fuel-efficient vehicles. Be sure to keep your wallet close by as the gas pump will be a regular fixture. This luxury sedan is a reminder of an era when automotive manufacturers pushed the boundaries of what was possible, creating legends like the Audi S6 V-10 that continue to captivate and inspire to this day.

Design And Styling: Aesthetics And Functionality

Audi took a subtle approach to the design and styling of the S6. The higher-performance S6 variant does not look significantly different from the standard A6 model. The front fascia is dominated by a long hood housing the massive V-10 engine with the traditional quad-ring grille. The unique identifying characteristic on the front fascia differentiating the A6 from the S6 is a pair of five LED lights one on each side of the front bumper.

Exterior design is for the lack of a kinder word, bland at best. Despite packing a Lambo heart under the hood, except for V-10 badging on either side of the vehicle, the S6 could easily be mistaken for the less sporty A6 variant. The rear of the car doesn’t deviate much from this theme, with the primary design highlight being the presence of quad exhaust tips.

The interior of the S6 screams opulence with leather seats, and aluminum and birch wood accents for a full premium luxury experience. The S6 showcased remarkable technological innovation ahead of its time in 2008, boasting features such as a voice control system, an infotainment interface operated through a center console rotary dial, and adaptive cruise control. In comparison to some contemporary budget sedans, the Audi S6 from 2008 was exceptionally advanced in terms of its practical technology, putting even modern vehicles to shame.

Ownership and Maintenance: Living With The Audi S6

Owning an Audi S6 comes with its unique issues that no model is immune to. The 5.2-liter V-10 engine is notorious for valve cover oil leaks that can cause engine misfires and oil odor transfer into the cabin when running the AC. The intake ports can get carbon built on the intake valve causing leaks and poor performance, this typically happens approximately every 50,000 miles.

Suspension bushings are known to also deteriorate with age causing harshness in ride and a noisy drive, this issue can easily be solved by replacing all worn-out bushing. Anyone in the market for a more-than-decade-old German luxury sedan should expect a laundry list of issues that may need immediate or deferred repairs.

This however should not scare you off entirely from owning this V-10 luxury sport sedan. It’s important for prospective buyers to check for the following list of Audi S6 issues before committing to a purchase:

• Engine Overheating due to a failing thermostat
• Check engine light due to faulty torque converter
• Oil leak from transmission output shaft seal
• FSI and TFSI Engines Carbon Buildup (Intake Valves, Intake, Runner Flaps P0300 series
• Rainwater May Accumulate in the Plenum Tray Due to Clogged Drains

The V-10-Powered Audi S6 And Its Rivals

The Most Understated, Yet Most Exotic European Luxury Sedan

The European luxury car segment is one of the most competitive market spaces in the automotive markets. With brands from all over the world crafting four-door sedans that feature mighty four-bangers, raspy straight-six engines, some of the greatest European V-8s ever made, and even V-10 and V-12 engines, this segment has an endless amount of options. That said, very few are as unique as the C6-generation Audi S6.

While the S6 wasn’t the only luxurious sports sedan to feature a V-10 engine – the E60 BMW M5 also exists – it’s hands-down one of the most deceptive ones. Despite its long list of issues and uninspiring exterior design, the C6 S6 remains a favorite among enthusiasts who crave a sleeper car in their collection. And for an average used price of $13,812, as per Classic.com, the Audi S6 is also one of the cheapest and most underrated sports sedans you can buy from the 2000s.

Comparing statistics next to each other, it’s clear that the Audi S6 can’t quite keep up with some of these V-8 sports sedans that still pack a punch. Everything considered though, the Audi S6 remains the cheapest and is the only sedan that sourced its engine from a Lamborghini supercar.

Summing Up The Audi S6

Building upon the solid foundation of the A6 platform, Audi elevated the sedan in all the areas that truly matter, most notably by equipping it with the astounding V-10 engine. While it’s true that one could argue that other cheap Mercedez-Benz models such as the E500 boasted more power and quicker 0 to 60 mile-per-hour time, such arguments quickly lose ground when considering the S6’s true purpose.

The Audi S6 wasn’t designed to be the absolute fastest among the German super sedans; rather, the S6 was the engineering equivalent to a street flex. Audi showed off in a way that wasn’t over-the-top, or in a way that would attract the attention of everyone, but rather in a way that just shook automakers’ boots a tad.