Premium or Standard Unleaded ?

[Lord Sladacre]

Can members advise please? Should I run my 3.0 litre, 2003 S - Type auto on the premium or standard grade unleaded? My practise has been to give it a tank full every so often of the "good" stuff - as i have read it keeps injectors and other bits in more efficient and clean condition. The difference in Dorset is not fantastic in terms of cost approx 15p per litre - £9.00 on 60 litre tank full. As I am about to cover 1000 miles to Northumberland and seemingly all points in between I would like to be sure I'm doing the right thing. Currently, on a 200 mile run, with cruise control used when roads dictate, at 80 mph  - average 55 mph, I manage an astounding 37 mpg !! - and that is on a mix of fuel ! Your thoughts would be much appreciated, thank you, Dominic

[Old Peter]

Hi Dominic,

My s type is a 2.7 diesel and I always us shell V power --  premium.  It seems to suit the diesel engine, especially on a long run where my average performance is circa 46 mpg with a record 50.2 mpg on the M1 when there was a 50 mph speed limit for 45 miles.  But a diesel is much different from the petrol engine.

37 mpg for the 3.0 litre engine does sound very good and keeping the fuel system cleaned can save a big bill.  I would be inclined to use the premium fuel for a a while a see if you can feel the difference.

Regards,

Peter.

 

[Jon Hyde]

Hi Dominic,

I also always use premium diesel in my 3.0l XF, after Peter posted his advice (thank you Peter!).

The effect isn't just more mpg (which there are!), but a smoother, more responsive engine. I also put in a shot of Millers Oil Eco Max additive every second fill up. 

My SWMBO has an Audi TT (which used to sound like a tractor on startup) and she is now converted to premium diesel which had made it more acceptable.

Either way, enjoy your Jaguar and avoid Audis at all costs 🙂

Cheers,
Jon

[Old Peter]

Hi Jon,

I have spent 20 years avoiding Audis.  I think the Owners Manual for Audis reads:-

1.  Disregard all speed limits.

2. Tailgate whenever possible, especially in built up areas, and motorways.

3. Never use trafficators.

4. Cut corners.

5. And when parking make sure you park on double yellow lines.

Peter. 

[Lord Sladacre]

My thanks to Old Peter and Jon for your excellent advice gentlemen. I'm sure that you are right and I will feel more comfortable in the sense that I'm doing the right thing for the car  is always using premium grade fuel. As I have said I think for a 3 litre  petrol engine (six speed auto box no doubt helps) the fuel economy is fantastic.  I manage between 34 - 37 mph on a good run. It will be interesting to see what the car achieves from Dorset to Northumberland via Lincoln and York !! 

[Pugheaven]

I've always usd premium in all my cars, RX8, Mazda Xedos 9 2.3 Super charged and others... just runs better and more MPG. I'll continue with my new S-Type 2.7.

[Lord Sladacre]

Hi Mark,

 

Many thanks  - sound advice, I have decided to follow the advice of the wise, whom appear to be many. Premium only from now on !!