Yeah, diesels are pretty much everywhere but here in the US.

 

This is great information and it is absolutely correct that the Disco manual states premium fuel. Technically speaking, the Discovery 1 & 2 are blessed with a low stress, low HP, push rod engine that was designed in the early sixties by General Motors Buick division. This is what makes it a great engine, no timing belt to worry about, no variable valve timing, just a solid all around power plant. Maintain it right and you can get 200 K Miles easily.

The owners manual in my M5 6 speed (4.9 L V8, 394 HP /6800 RPM) states premium fuel and BMW is very serious about it. You try to use 87 octane and it cuts back your RPM at the first sign of pinging. The M5 is even picky about the premium brand, BP or Texaco.

The new Range Rover uses the same BMW V8 (4.4 L) and some are supercharged, in that application you must use premium, absolutely.

For the disco 4.0 L, I am not convinced yet. May be the 4.6 L is different.

 

I use premium because of the following:

1. Too many problems documented by others who chose low octaine gas.
2. I plan to keep my Disco for many years and am investing in many off road mods.
3. I did not buy this car for gas mileage, I bought it for off roading and a save on road drive.
4. My wife's paycheck is based on the oil companies making a profit so my buying premium is a good investment!

And if gas ever gets just too high in cost I will buy a hybrid or Smart Car for around town driving and save my Disco for the fun stuff!

 

Lots of fuel containers.

 

I currently run premium in mine because when I bought it was the day gas became real scarce around these parts, and all I could find for like three weeks was regular. As soon as premium was available again, I noticed a huge difference. I am still contemplating fabbing and installing an HHO generator. Just haven't quite ironed out all the kinks as far as parts availability and making the o2 sensors get along with the leaner burn of the HHO system.

 

How about average miles per gallon.

My MPG including city and hwy driving is at 15 MPG. Actually it varies between 14.7 and 15.8. using 87 octane.

In comparison with the rest of the fleet, is it Good / Average / Low???

 

that's probably about average, but think about where you'd be if you used premium? you could hit 19 mpg average on 93 if you're getting 15 on 87

 

i get 15mpg towing my boat (1 ton) going 55 on the highway. so i would say your lower, Also if you don't use premium, your just kind of stupid. I don't know where your filling up, but my 91 octane is only 8-15 cents more then 87. i use Exxon, BP, or shell. $1200 for premium beats new valves or new head gaskets, plus the improved performance is great.

also if you can find gas with no ethonal use it! you gain 1-3 mpg! ethonal is such a scam....

 

Snowdude, in NC if you drive at 55 on the highway you get run over.

On the highway, you got to do 78+ to keep up with the traffic. My SD loves to cruise at 80+.

Regarding prices, please check the web, lowest price in NC for regular is $ 1.72 and premium is $ 1.97, today. The difference was much higher when prices were at $3.00 not long ago. I am not sure what is going with gas prices in North East Wisconsin.

Regarding MPG, EPA rates the 4.0 L DII at 13 MPG city 17 MPG hwy. It will be great if one can get 20 MPG. Maybe an HHO kit that was mentioned earlier will do the trick.

 

keep in mind the EPA ratings are always ultra conservative, and can be off as much as 3 MPG on the low and high number.