AUDIíS RS6 ALL-WHEEL drive superstar expanded on the smaller RS4ís appeal by being available in both five-door estate (Avant) and four-door sedan guises. And with each one powered by a 4.2-litre twin-turbo V8 pushing out 331kW, the RS6 was a top driverís car.
Combine all that power with the four-wheel drive grip of Audiís legendary quattro set-up and you had a machine as capable on the twisties as it was in a straight line, with torque routed from the gearbox output shaft to the Torsen centre diff before being automatically divided and apportioned between the front and rear axles.
Although the RS6 isnít all about performance and handling capability, sharp, well-weighted steering and impressively compliant ride quality are in there, too.
This is a highly usable, high-performance machine that doubles-up as a tame daily driver Ė of course, thatís if you can afford the fuel bills.
If the 331kW output of the regular RS6 isnít enough, you need to check out the limited-edition Plus model that arrived in 2004 (solely in Avant guise), which pushed power to 353kW (and top speed to 280km/h) thanks to an uprated ECU and modified intercoolers. But even a standard RS6 will take you to 100km/h in less than five seconds en route to an artificially limited 250km/h top speed. When buying any C5-gen RS6, a comprehensive service history is essential; if itís patchy or missing altogether, then walk away. This is a complex machine that relies on proper maintenance, but servicing can be pricey. Even a low-mileage car needs a full going over every year Ė and itís essential that the cambelt, tensioners, waterpump and thermostat are changed every 4-5 years (or 65,000km if that comes first) without fail. The V8 itself is a robust powerplant that takes high mileages in its stride, with few reported problems other than failed intercoolers on high-use examples. '
The RS6 came with a ZF five-speed automatic transmission as standard, ensuring it was as effortless to drive as it was thrilling. Itís generally reliable, but has been known to fail completely if neglected. When checking an RS6ís service history, make sure the transmission has had an oil and filter change at least every 65-80,000km. Check that gear changes up and down the íbox are smooth and that (once warm) the lock-up clutch engages as it should. An exchange gearbox from Audi can cost more than $7250 plus fitting.
The RS6 was fitted with Audiís then-new Dynamic Ride Control, a system of diagonally linked dampers in order to reduce pitch and roll. Itís highly effective, but can be prone to leaks Ė and with the cost of replacing all four shocks with factory originals being anything up to $5500 including labour, itís a pricey failure. Many RS6 owners choose to replace them with adjustable aftermarket coilovers (Bilsteins are a popular choice), which give great results Ė as well as being more affordable and potentially more reliable.
Rust shouldnít be an issue with a well cared for RS6 Ė but an abused example can suffer in other ways. Are there any signs that the carís been in an accident? Check for subtle difference in paint shades and panel gaps that donít look perfect. A car thatís been thrashed, trashed and poorly repaired needs avoiding at all costs.
Also look underneath for evidence of damage, as well as in the engine bay. Are all the structural sections original and free of creases? Ensuring that any RS6 isnít a previous write-off is obviously vital and easily done.
How long your RS6ís brakes last will depend entirely on your driving style Ė you might get up to 30,000km out of a set of pads if youíre careful. When looking at a potential purchase, check the state of the pads and cross-drilled discs and ask when they were last changed. Replacing a full set of discs can cost you $2700-plus, so be vigilant when inspecting any RS6.
The Audiís super-sharp steering adds to the carís driver appeal, and should bring few worries in terms of reliability. Carry out the usual checks for leaks and any strange noises on full lock, but otherwise all should be well.
As youíd expect of an Audi, the RS6 came with a highquality interior that wears well, even on well-used cars. Youíll obviously need to check for wear to the leather (particularly the side bolsters of the front seats) but it would be unusual to find one thatís not in good order. Make sure the general condition of the interior (particularly the steering wheel, carpets and so on) tallies with the mileage of the car.
Exterior trim can suffer, with many RS6s having attracted minor parking scrapes to their bumper corners, arches and sills by now Ė so check for signs of damaged paintwork and recent spraying.
YOU WANT to make your RS6 even quicker? ECU remaps arenít unusual, often adding 20-45kW depending on the spec. Companies like APR here in Australia have numerous tuning options (including ECU upgrades and intakes) for your C5 RS6. A bespoke aftermarket exhaust will also add a touch more power and responsiveness.
You can also opt for a boost leak testing system to check if the bi-turbo 4.2-litre V8 is losing any power over its factory 331kW/560Nm claims. A tiny hole in either of the intercoolers or charge piping or leaky connections will be found.
If your RS6ís suspension is starting to show signs of age and wear you can opt for fully adjustable coilovers (there are a range of brands to choose from), with front and rear adjustable anti-roll bars helping to improve the carís handling further.
BODY 5-door, 5-seat wagon
DRIVETRAIN front-engine, all-wheel drive
ENGINE 4172cc V8, DOHC, 40v, twin turbo
POWER 331kW @ 5700-6400rpm
TORQUE 560Nm @ 1950-5500rpm
TRANSMISSION 5-speed automatic
A naturally aspirated 5.0-litre V10 sending 373kW to the rear wheels only via a seven-speed, singleclutch semi-automatic sounds pretty good, right? Sadly, itís the only one out of this trio not to come to Australia. Some markets even got a manual, too.
The traditionally Ďsafeí marque packed an angry 2.5-litre five-cylinder turbo and all-wheel drive (with six-speed manual or five-speed auto) into its V70 to make the R. Its power figures of 220kW and 400Nm made it the fastest Swede of its time.
Despite hitting the scales at two tonnes, this dogcarrying mega Merc had a supercharged 5.4-litre V8 to allay any fears of a lack of performance. With 350kW/700Nm heading to the rear wheels via a five-speed auto, it made any school run a breeze.