Models · Audi
Audi RS6 Avant and RS7 Sportback C8 buying guide
The C8 RS6 Avant and RS7 Sportback arrived in 2019 with a 4.0-litre twin-turbo V8, mild-hybrid assistance, an eight-speed automatic and quattro. The drivetrain is strong, and the known issues are mostly electrical, plus a handful of recalls to confirm.
The versions
- 4.0 TFSI twin-turbo V8 with 48V mild hybrid and cylinder on demand, 600PS
- Performance: 630PS from larger turbos and more boost, replacing the standard car rather than sitting beside it
- RS6 GT: a limited carbon-bodied edition, about 60 for the UK
- ZF 8-speed torque converter automatic with quattro and a Torsen centre differential; sport rear differential standard in the UK
- Air suspension as standard, with steel springs and Dynamic Ride Control as the alternative (Vorsprung cars came on steel springs)
- RS6 Avant estate and RS7 five-door Sportback, sharing the 4.0 V8
What to check on a C8 RS6 or RS7
3 model-specific things to look at when you view one. They're a starting point, not the full inspection.
Sport rear differential
What to look for: From underneath, or with a torch behind the rear wheels, look at the rear differential casing in the middle of the back axle for fresh oil or wet grime.
Why it matters: The sport rear differential fitted as standard to UK cars can develop an oil leak. A dry casing is what you want to see.
Mild-hybrid electrics and the alternator
What to look for: With the engine running, watch the dashboard for electrical or engine management warnings. Ask whether the battery has ever gone flat and whether the alternator has been replaced, and look for it in the invoices.
Why it matters: Battery drain causing engine management problems is the most common complaint about the mild-hybrid system. Alternators on this platform have a reputation for failing, and Audi extended the warranty on them, so check whether this car has had one.
Misfires in damp weather
What to look for: On the drive, accelerate gently at low revs in the middle gears and feel for any stutter or hesitation, especially if the weather is wet. Note any flashing engine warning light.
Why it matters: Some cars have misfired at low revs in mid gears in damp conditions. Injector and spark plug work hasn't always cured it, so ask the seller whether it has ever happened and what was done.
Also in the full guide
- Recall work
- Tailgate, door locks and other motors
- The cold start, test drive and paperwork checks for the exact version you're viewing
The full guide to the C8 RS6 or RS7
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 C5 · Audi RS6 C6 · Audi RS6 Avant and RS7 Sportback C7
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.