By the time the Jaguar XJ40 finally appeared in 1986, it had been in development for so long that you half expect the early sketches to have been done on parchment.
Work on replacing the original XJ had begun back in the 1970s, but this was Jaguar, British Leyland, oil crises, industrial trouble, privatisation and luxury-car expectations all fighting for space in the same glovebox. Nothing was ever going to be simple.
The result, when it arrived, was a car that looked both familiar and slightly startling. The XJ40 was still unmistakably a Jaguar saloon: long, low, dignified, with the sort of presence that suggests its owner may have strong views about cufflinks. But it was also more angular, more modern and more 1980s than the Series III it was designed to replace. The old XJ had curves. The XJ40 had shoulders.
Launched in 1986 and celebrating its 40th anniversary in 2026, the XJ40 had a difficult job. Jaguar couldn’t simply throw away everything people loved about the XJ. The shape, the ride, the cabin atmosphere and the sense of occasion all mattered. At the same time, it couldn’t keep building the same car forever, however beautiful it was. Rivals from BMW and Mercedes-Benz weren’t sitting around admiring walnut veneer. They were getting sharper, faster and more technologically confident.
So Jaguar tried to modernise without losing the magic. That’s a dangerous business. Change too little and everyone calls you old-fashioned. Change too much and people say you’ve ruined it, usually while standing next to the old one at a show.
The XJ40’s styling was the most obvious shift. Early cars were available with rectangular headlamps on some versions, while others kept round lamps for a more traditional Jaguar face. It’s a small detail, but it says a lot about the car’s identity crisis. One eye on the future, one eye on the club members muttering into their tea.
Inside, the XJ40 also tried to move things forward. It brought digital displays, onboard diagnostics and a more modern electrical architecture. This was Jaguar embracing technology, which sounds exciting until you remember that 1980s electronics and British luxury cars didn’t always enjoy a peaceful marriage. Early cars developed a reputation for electrical niggles, and the digital dashboard could make the XJ40 feel less like a gentleman’s carriage and more like a fruit machine with leather seats.
Still, the ambition was real. The XJ40 was the most extensively tested car Jaguar had produced up to that point, and it was designed to be easier and more efficient to build than the Series III. The body used fewer pressings, the structure was stiffer, and the car was intended to mark a serious step forward in production quality. That last bit didn’t always go perfectly, but the plan was sound.
There’s also a wonderfully odd story about the engine bay. It’s often said that Jaguar’s engineers deliberately made the XJ40’s front structure too narrow to accept a V-engine, partly to prevent British Leyland from forcing the Rover V8 into it. Whether one treats that as hard fact or splendid folklore, it’s exactly the sort of story that suits Jaguar: elegant people in Coventry quietly designing around corporate interference with the engineering equivalent of a locked door.
At launch, the XJ40 used Jaguar’s AJ6 straight-six engines rather than the old XK unit, which had served the company since roughly the dawn of ration books. The V12 would eventually arrive later in heavily reworked XJ81 form, but for the early XJ40, the six-cylinder cars were the main event. They suited the car’s character rather well: smooth, refined and properly Jaguar without feeling ancient.
It wasn’t all smooth sailing, though. Early build quality issues hurt the XJ40’s reputation, and the long development time meant some rivals felt newer almost immediately. The BMW E32 7 Series arrived in the same era, Lexus changed the luxury-car conversation with the LS400 in 1989, and Mercedes-Benz continued being Mercedes-Benz, which must have been irritating.
Yet the XJ40 deserves more affection than it sometimes gets. It carried Jaguar through a crucial period: post-British Leyland independence, privatisation, then into the Ford era. It was also one of the last Jaguars developed with Sir William Lyons still involved in the background, and he reportedly saw and approved the final prototype before his death in 1985. That gives the car a certain closing-chapter poignancy.
Today, the XJ40 is an interesting classic because it sits between worlds. It isn’t the old romantic Jaguar of smoky gentlemen’s clubs and chrome bumpers, nor is it the later Ford-improved Jaguar of smoother quality and retro polish. It’s the awkward bridge between them – ambitious, handsome, sometimes frustrating and much cleverer than its reputation suggests.
Forty years on, the XJ40 feels like a car worth reassessing. Not perfect, no. But important? Absolutely. It was Jaguar trying to step into the future without spilling the whisky.
