Models · Audi
Audi RS6 C5 buying guide
The first RS6, built from 2002 to 2004, uses a 4.2-litre twin-turbo V8 developed with Cosworth, a five-speed Tiptronic automatic and quattro, in Avant and saloon forms. It introduced Dynamic Ride Control, and most of its known issues are well documented by specialists.
The versions
- 4.2 twin-turbo 40-valve V8 (BCY), 450PS
- RS6 Plus (2004, Avant only): 480PS (BRV), lower Sports Suspension Plus and a higher speed limit
- 5-speed Tiptronic torque converter automatic (ZF 5HP24A); no manual was offered
- quattro permanent four-wheel drive with a Torsen centre differential
- Avant and saloon bodies, with Dynamic Ride Control suspension as standard
What to check on a C5 RS6
3 model-specific things to look at when you view one. They're a starting point, not the full inspection.
Dynamic Ride Control dampers
What to look for: Look behind each wheel at the dampers and the pipes running from them for oily wetness. On the drive, feel for a bouncy or unusually harsh ride and listen for knocks. Ask whether the original system is still fitted.
Why it matters: Dynamic Ride Control links diagonally opposite dampers hydraulically to resist roll and pitch. The dampers commonly leak, and a failure can affect the central valves. Specialists replace them across an axle or as a set. Many cars have been converted to conventional dampers, which is a legitimate fix; ask what's fitted.
How the gearbox shifts
What to look for: On the drive, accelerate firmly through the gears and feel for slipping, revs flaring between gears, harsh or delayed shifts, or a shudder at light throttle. Check the history for gearbox fluid and filter changes.
Why it matters: The five-speed Tiptronic was close to its torque limit even at standard power, and the gearbox and torque converter are the weak point of the car. Specialists change the fluid and filter every 40,000 miles. A smooth gearbox with that in the history is reassuring.
Cambelt and water pump history
What to look for: Look in the history for the date and mileage of the last cambelt and water pump change.
Why it matters: The V8 has a cambelt, and the front of the car comes off to change it. Specialists recommend replacing it with the water pump about every three to five years or 35,000 to 40,000 miles, and many replace sensors while the front is off. An overdue belt is a job to plan for.
Also in the full guide
- Boost leaks and the turbos
- Water in the cabin and the fuse box
- Oil and coolant leaks
- The cold start, test drive and paperwork checks for the exact version you're viewing
The full guide to the C5 RS6
The CrankSight guide walks you round the car on your phone at the viewing, with every check for the exact version you're looking at: what to look for, where to find it, and what anything you find is likely to cost. As you go it builds an assessment of that car, and if you view more than one, it lines them up side by side.
£29 for the model, used on as many cars as you like, delivered within 72 hours or your money back.
Other generations
Audi RS6 C6 · Audi RS6 Avant and RS7 Sportback C7 · Audi RS6 Avant and RS7 Sportback C8
General points for the model, last checked October 2026. Every car is different, so treat this as a guide to what to look at, not a verdict on any car. CrankSight is independent and has no connection with Audi.