Just done a 300 miles trip and was astonished to find that doing an average speed of 58 mph I averaged 25.8 mpg, not bad for a supercharged V8. New plugs, ATF, air filter, and most importantly a light right foot may have had something to do with it. My XJ40 only ever manages 23 MPG.
Anybody done any better?
Cheers, Dave.
1990,XJ40[fast]
2000,XKR[scary fast]

 

Oh yeah. I've got a solid 24 average (mostly freeway) over the last 31 tanks since the beginning of the year. Now getting heavy on it around town will bring it into the teens...
Mike

 

Except its not uncommon for the newer 4.2 xj's to get 30-33mpg

 

Yeah, I looked at my first '05 XK8 on Tuesday.
Just thinking ahead...

 

I get 30-31 with the cruise set at 75mph on my 04 XJ8 all the time.

 

On long trips I average 27 mpg and that's with a few bursts from cruising speeds in the 70 - 75 range up to 110 -120. This is in a normally aspirated XK8, one person in the car with minimal luggage.

 

In my '02 xk8 at 60mph I get 30mpg but damn it's hard driving at that speed

 

I'm environmentally conscious. A Prius is a gimmick. Sadly, far too many Americans have fallen for it.

 

I drove 1000 miles from Dallas at about 78 MPH and averaged 19.6 which I considered pretty good milage

 

Let's just call a spade a shovel... we didn't buy these cars for the miles per gallon but rather for the smiles per gallon.

 

Prius proven to be as efficient as a Discovery in long term .

 

By the sounds things my 25 mpg is about average for relatively careful motorway driving. Do you think that we grow wiser with age or just more tolerant. I mention this because over the years I have noticed that driving a Jaguar of any kind, and not intending to sound in any way superior here, seems to instill a desire in some other road users to prove they have a better and faster car.
So bearing this in mind I find this quote to be very acurate. Trying not to react when some silly person tail gates you just to get a closer look at your new paint job, or "White Van Man" a name we give to all Cro-Magnon delivery drivers, here in the UK, decides his Ford Transit is in actual fact a GT40 with space and cuts you up, demands a great deal of control by us Jaguar drivers.
Even with age and maturity, the red mist sometimes decends and you just have to unleash the Jaguar beast and bang goes the 25 mpg...
There again thats why I drive a Jaguar and not a prius.
Cheers, Dave.
1990 XJ40[fast]
2000 XKR [scary fast]

 

Just a reminder guys, Boztron's imperial gallon is 1.2 times our US gallon. His 25.8 imperial mpg sounds right on the money as 21.5 US mpg for a 2000 XKR carefully driven !

 

True enough, My car indicates 20.0 mpg average for urban/highway driving.

 

I'm getting 16mpg combined and 19mpg highway while averaging high 70mph. Not good but quality of ride is 1000% better than those Prius poseurs.

 

Life is too short to worry about MPG.
just drive your Jag the way you should.