Daimler Double Six Review is a Fun Peek at Jaguar History

By John Coyle - January 21, 2022

During development of the XJ40, Jaguar got creative to thwart interference from the brass at British Leyland.

The British automotive industry has seen more than its share of drama, and while the pandemic has temporarily overshadowed Brexit, there’s certainly more to come. That said, I love stories about the bad old days, and James Martin’s review of a well-preserved Daimler Double Six revealed something I never knew about the development of the fourth-generation XJ. Apparently, while Jaguar was still under the umbrella of British Leyland, the brass at Coventry feared interference from above — and took dramatic steps to prevent it.

Now, while the XJ40 was still on the drawing board, there was concern that Jaguar would be forced to use corporate cousin Rover’s V8 engine in the new saloon. As Martin points out, with the extra pots and compatibility with Jag’s General Motors-sourced automatics, the mill would have actually been a good fit for the car. But apparently, the powers that be at Jaguar wanted none of it, as they thought it would lead to the complete death of the company’s in-house powertrain development. So they simply ensured the XJ40’s engine bay was to narrow for the Rover unit.

As obstructive tactics go, it was impressive — though it left them with another problem. Because other high-end luxury sedans from rivals like Mercedes and BMW had eight, or even 12 cylinders, and Jaguar wanted to be able to compete. The solution was to utilize the chassis of the Series III cars, fit them with the range-topping V12, and brand them as Daimlers. Thus, the Double Six was born. Aside from small touches like square headlights and beveled trim on the grill and decklid, the exteriors were essentially identical to the Jags, but under the hood, the changes were more noticeable.

Chief among the changes was the fact that, along with some additional displacement, Daimler buyers were treated to a far tidier engine bay. As opposed to the mess of plumbing folks faced when they popped the hood of 12-cylinder XJ, the Daimler cars are the picture of elegance, and even today, the presentation of the engine looks decidedly modern. Whether they were any easier to service is unclear, though if I had to guess, I’d bet that got worse instead of better. Check out the video for a full tour of this lovely old luxury sedan, and if you happen to own one of these babies, make sure to post some pics!

Photos: YouTube