Believe it or not, our BMW X5 3.0sd has finally given us something out of the ordinary to write about.

Until now, all we have been able to do is report on how this fine vehicle drives, how efficiently dynamic it is, how easy it is to live with and what it's like to drive perhaps the finest road-going turbodiesel engine in the world.

Long-term tests are about bringing out the best and the worst in a car and we were becoming a little worried that all we could do was praise this delightful car ? surely there has to be something else to write about?

And it's happened at last ? we have a problem with the X5!

In truth, it's a tiny problem, but it's still a problem and it does give us something else to talk about...

Here's what has happened: a reinforcing member under the driver's seat has become loose and fallen down on one end so when the seat was moved to allow Carol to revert to her regular driving position, following my changing it to accommodate my bulk, the seat jammed.

Yes ? that's hardly anything to write home about, but, please understand, it is something to write home about!

I suppose that's testament to the level of perfection we've come to expect from BMW ? that even a small problem is big news, because you just get so used to no news in the first place...

For the rest, the sd just carries on delivering that sublime blend of V8 performance and turbodiesel consumption and emissions. It has the ability to run with a Golf GTI despite being an almost two-ton car. Quite stunningly, it delivers fuel consumption ? and real-world CO2 emissions ? of a car half the size.

Talking fuel consumption, the numbers shown among the data on page two represent pretty much full-time urban driving. The car has spent most of the past two months on the school run, running errands and dealing with the everyday challenges of Joburg traffic.

Our routine sees very little freeway driving, if any at all, and the plusses gained from our country trips over the holidays are ancient history now. Still, at 14.5 l/100km in those conditions, this is a far better bet than the 20-plus l/100 a V8 will achieve in these conditions. On top of that it gives you a tank-to-tank range of almost 600km.

And it does so in absolutely stunning style, with the poise of a saloon and with the convenience and versatility of a full-sized sport activity machine (as BMW likes to call it...).

We're also quite excited as we understand our replacement X5 is on the way. It may have a new name in X5 xDrive 3.5d but, in truth, it's just a new name ? sd is no more and the 3.5 bit is also quite confusing as the engine also remains that brilliant 3-litre twin-turbo diesel.

But the newcomer will have all the spec you can pile into an X5 and we're looking forward to experiencing that extra seven-seat versatility, the sunroof and fully electric seats among other niceties.

Somehow, I reckon they won't be getting that one back...