Just done my first decent run in my new to me 2.2 ltr diesel. Bought it at Christmas with 60.000 on the clock.
I had read that this motor could be economical but 61.5 mpg on a 350 mile round trip really pleases me. This was at motorway speeds and from cold. Have to now do a full tank to full tank test to see if it agrees with the electronics.

 

That's very nearly 3 times better than my XK!

Graham

 

AAh but yours is a XK!!!

 

I've only had one Jaguar XJ12 - that was a 1972 pre 'HE' 5.3 litre model. Rarely getting into double figures for consumption, it went the journey after six months. After that anything seems relatively economical.

Graham

 

KIN OUCH!

 

Although I only have the 2 litre X-Type on an 09 plate which I have had from new, I regularly see 55 MPG as an average, so the figures you are seeing does not surprise me as you have an extra gear (6 as opposed to my 5) and you can run at slightly lower revs because of that extra gear.

But even so, I have always been very happy with my mileage return.