It’s hard to believe that in the 36 years that Range Rovers have been around, they’ve never had a dedicated diesel engine all of their own. Until now they’ve always used bought-in diesel engines from other manufacturers and, frankly, they’ve always felt a bit limp. So behind the scenes Land Rover has been working on a V8 diesel-burner just for itself, complete with a pair of fashionable variable-geometry turbochargers.

The result is a completely new engine that produces over 40 per cent more power and torque than the current V6 diesel, and while the performance goes up several notches (0-60mph in 8.6sec instead of nearly 12), it’s the astonishing refinement that really impresses.

This really is a diesel engine that doesn’t know how a diesel is meant to behave; 99 per cent of passengers will never know it’s burning ‘farmer fuel’. If they’re sitting in the back you can make that 99.9 per cent, as that’s where you can hear the burbling V8 rumble coming from the twin exhausts. Diesel off-roaders aren’t meant to sound like this. In fact, it’s even more refined than the full-size Range Rover fitted with the same engine, but that’s another story.

The TDV8 Range Rover Sport gets the brakes and suspension from the supercharged petrol-engined version, meaning stronger four-pot Brembo front brakes and stiffer roll resistance thanks to a tweaked Dynamic Response anti-roll system. It needs it, though, as the downside of this new 3.6-litre V8 is that it puts the kerb weight up to 2675kg (220kg more than the V6), with most of that weight concentrated over the front axle, although the revised chassis disguises this extra bulk rather well.

It’s not only the engine that’s been piling on the pounds – the list price has gone up significantly too. A TDV8 in HST spec (as I drove) comes in at £59,020, which is £11K north of the V6 diesel and well into supercharged V8 Rangie Sport territory. Yet it’s there where it starts to make sense. A potential 25mpg rather than 15mpg makes a big difference in the real world.

This may not exactly be a ‘green’ Range Rover, but at least it’s a start.