mine from yesterday...
tire pressure 32/34

 

Same on highway. 20ish in town

 

I don't trust the computer personally. Mine usually says 23/24, but if I calculate it myself it comes out as 21. That's with an average speed in the mid 30s.

 

In July this year my wife and me took a little trip to Mexico beach Florida from our home in Mississauga Ontario Canada, to visit my young sister, in the 9 days we were away we covered around 3,000 miles, At each fill up I checked the fuel consumption compared to what the car said and it was pretty close, 36 mpg, very pleased with that, my last car was a 1998 vdp and it struggled to get 30mpg.
cheers
Dave
2007 xj8.

 

Average speed 60mph.
The most I have seen it 35mpg so far.

 

Given that you're in UK, your 34.3mpg is equivalent to 28.6 US mpg.

Sorry mate

 

My N/A 04 get's 32~33mpg regularly @ 70mph road trips here in the southern US. I always use 91~93 octane Phillips66, Valero, CONOCO, Sinclair which is ethanol free Top-Tier.

 

I am well aware of the difference between US gallon and UK, would this not apply to dvjag too as I believe Canada use the Imperial gallon too. You asked for my highway mpg and that is what you got. Your MPG is impressive, I would love to find out what mine could do on much longer roads.

 

Recent highway run = 26.0 mpg

Thanks-
Mag

 

On the dash I'm always looking at 20.something around town and I figure it with a calculator every time and write it down.. The car computer is always within 2 tenths of gallon.. On the highway across Florida 70-80mph I get an honest 27-28mpg.. I love this car

 

Did a trip last week from Dallas to Austin then back.
On the way there I had cruise control set at 75 and got 29 mpgs. On the way back to Dallas I averaged 31mpgs. 04 XJR.

 

Had another go today, though I did drive slower this time and avoided quick acceleration. Not really representative of the way I drive (why I bought the S/C version), but interesting to see what is possible, UK MPG btw.

 

32-34 mpg at around 70 mph. Normally I'll set it on cruise control and let the car do the work.

 

I fueled up last night and over my last 310 miles, I averaged 17.4 miles-per-gallon.

I use the Fuelly Gas Tracker app and log all my fuelups. The best I have ever done between fuelups is 21.2 MPG.

 

My Super V8 gets 25 highway 20 city according to math. Trip computer reads 1MPG higher. Pretty good.

 

My experience as well.