Parkers overall rating: 4.8 out of 5 4.8

Miles per pound (mpp) Miles per pound (mpp)

Petrol engines 4.7 - 4.9 mpp
Low figures relate to the least economical version; high to the most economical. Based on WLTP combined fuel economy for versions of this car made since September 2017 only, and typical current fuel or electricity costs.

Fuel economy

Petrol engines 22.1 - 22.8 mpg
  • Old V8 retained, but with mild hybrid technology
  • Mild improvement in CO2 and MPG
  • Less thirsty than the last Audi RS6

The main difference between this and the last RS 6 Avant is the adoption of a 48-volt mild hybrid system of its twin-turbo V8. A belt alternator starter means that up to 12kW can be recovered when your foot's off the gas, which is then stored in a small battery pack for when extra power is needed – or when assistance is needed in town. When driving, the RS 6 can coast for up to 40 seconds with the engine switched off, thus saving fuel.

Don't get us wrong, this won't make it as economical as a Toyota Prius, but it does mean that it's making the most efficiency possible when the driver doesn't need performance.

There's also a Cylinder On Demand (COD) system, which can deactivate cylinders 2, 3, 5 and 8 in the high gears by switching off fuelling and closing the valves – again to save fuel when maximum power isn't demanded. As soon as the driver needs that power back, coasting and cylinder shut off will be deactivated.

Audi RS 6 Avant 2020 engine

All of that means fuel economy of 22.1-22.6mpg, and a promised CO2 of 263g/km - both tested on on 21 inch wheels, which are an inch smaller than the UK standard. Not world-beating economy, but an improvement over the previous-generation Audi RS6.

Reliability

  • Tried and tested parts
  • Engine slightly tweaked
  • Still a few unknowns

Being based largely on the Audi A6 Avant should mean the RS 6 is pretty bulletproof - certainly in terms of interior sturdiness and the reliability of its shared parts, such as the two-screen infotainment system.

Granted that's reasonably new but Virtual Cockpit has been around for a while now, and although the engine is more powerful than before that's largely down to some turbo-tweaks, rather than a whole new block, for example.

It's also fair to say that for the majority of the time in the UK the RS 6 is going to be quite unstressed. There will of course be other times when it is significantly stressed. All-in-all we reckon the RS 6 will see you right through its lifetime, but keep and eye on this page for any developing gremlins.

Ongoing running costs

Road tax (12 months) £475
Insurance group 50
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