WHEN is a quattro not a quattro? The answer is when Audi deploys its new ultra quattro technology.

The result is an all-wheel-drive system that works only when needed and it makes Audi's latest Q5 SUV super-economical.

A claimed fuel return of 56.5mpg and a few other advanced features have impressed industry valuation experts CAP so much they say the new Q5 will be worth more than £23,000 after three years and 30,000 miles on the road.

That's an unprecedented figure which rates a top range 2.0-litre diesel Q5 quattro S line with an S tronic auto box at 58.3 per cent of its £40,220 ‘when new' list price.

Other standard features on the second generation Q5 include a power operated tailgate, 18-inch alloys and a multi-mode drive system while options include Audi's digitised virtual cockpit, a head up display and adaptive air suspension said to improve performance both on and off road.

When the new Q5 goes on sale in the spring it will be priced from £37,170 for a 190ps diesel and £37,990 for a 2.0-litre turbo petrol with 252ps on tap.

The Q5 has just made its North American debut at the Los Angeles Auto Show, not far from the border with Mexico where Audi is building its latest SUV at a new factory in Central America.

Production of the medium-sized SUV was switched from Germany to make way for the new Q2 compact model which has just gone on sale.