THE Leaping Cat has finally bounded into the sales jungle with all of its teeth bared. Jaguar has been slow to learn, but, at last, it has realised that diesel engines and estates really are quite popular. The only question, given that its all-new, diesel-engined X-Type Estate performs so well, is why did it take so long to produce one?

For 70 years, the classic British marque has dedicated itself to outrageously fast sportscars and cossetingly luxurious saloons. While that was happening, though, rival makers such as BMW, Mercedes and Volvo were winning customers with their supremely practical carry-alls powered by economical and sophisticated diesels. Diesel cars have come a long way since being rattling, smelly affairs and, in key markets such as France, Germany and Italy, are crucial if you want to sell in serious numbers. Even in Britain, sales are soaring.

No surprise, then, that the 2-litre diesel is, in many ways, the star of the all-new, X-Type Estate range. The four-cylinder diesel engine uses direct-injection turbo-charging and common-rail technology, all of which means that this relatively small engine produces 128 brake horse power yet will return an average 49 miles to the gallon — 19mpg better than the petrol version.

The target audience are the leisure freaks who glance at their wallets in the filling station on their way back from surfing or riding. And they will be impressed by Jaguar’s diesel estate, as well as a mite confused, for this is the estate that thinks it is a saloon. Jaguar has worked hard to make the estate drive as much as possible like the saloon X-Type. If anything, the estate is slightly quieter than the saloon on which it is based and lacks the echoing acoustics with which drivers of older estate cars might be familiar.

Jaguar has even put something called “vacuum stuffers” in the rear tailgate to reduce noise. Not only that, but its engineers spent many hours perfecting the tailgate so that when it closes it does not emptily “clank” but gives a more reassuring “clunk”. Jon Carling, the X-type programme director, said: “The estate sector is growing and not one we wanted to be left out of. (But) we had to take our time and make sure when we did launch our first production estate, it was perfect.”

Indeed, lift the tailgate, and the inside — carpeted, and filled with chrome fittings, as well as a power point to recharge your laptop on the move — seems far too posh a place to dump muddy wellies, damp labradors and sopping sailing kit. Carling is adamant, though. “This car is aimed at people who’ll play rugby rather than watch it from the terraces,” he said.

This estate is far more than a saloon with a shed bolted on the back: the car is new from the B-pillars back, with new rear doors, a new roof, increased stiffness as well as uprated suspension. The traction control and anti-lock braking systems have been re-designed for the estate. As well as the 2-litre diesel and petrol engines, there are also 2.5-litre V6 petrol and 3-litre V6 petrol engines in Sport, luxury SE and the more basic Classic equipment levels.

So to the diesel: if a “mere” 2-litre engine in a Jaguar seems an oddity, it need not be. The turbo-diesel has plenty of power with a top speed of 123mph (against 128mph for the 2-litre petrol) and a 0-60mph time just under ten seconds (9.3 for the petrol car). The diesel feels much sprightlier, though, because it has masses of torque — or pulling power — which means, that in almost any gear, the car will pull and pull, making it supremely easy to drive. It is also very quiet and only at the fuel pumps do you know this is a diesel.

The 3-litre petrol tops the range with Jaguar’s Traction-4 all-wheel drive. The big petrol car is far more powerful than its diesel sibling but, given the body is the same and load-carrying identical, is the better performance of the 3-litre V6 really worth the £4,700 premium over the similarly equipped 2-litre diesel SE? In normal conditions, the diesel has all you could wish for.

Despite its ability and the feel that this is such a blindingly-obvious addition to the Jaguar range, the company is conservative about its hopes for sales: Jaguar wants to take global X-Type sales from 60,000 to 75,000 with the addition of the estate and diesel engines. Hopefully, it will soon revise those estimates upwards because, 70 years in the gestation, Jaguar’s two new babies have been well worth the wait.

JAGUAR X-TYPE 2-LITRE DIESEL ESTATE SE

PRICE: £24,065 (diesel range starts at £21,165)

POWER: Two-litre, four-cylinder, turbo-diesel, for 128 brake horse power through five-speed manual gearbox

PERFORMANCE: 0 to 60mph in 9.8sec, top speed 123mph

ECONOMY: 36.7 miles to the gallon in town; 48.7mpg average

GOOD POINTS: Economical and practical luxury and all with the legendary Leaping Cat badge

BAD POINTS: We had to wait too long, allowing the German manufacturers to steal a march