Questions about Fuel

[94GolfTD-MK]

I have read/heard that Sunoco Gold Diesel is the best stuff to put in, but can someone please explain to me why?

What is the difference between lets say Sunoco Gold and Esso diesel, other then the 5-6 cent price different?

What do you guys find to be the best diesel?  I don't care about the few extra cents but I would like to know what I am paying for

Thanks
Mike

[QuickTD]

Diesel fuel quality is mostly about cetane ratings and lubricity. Cetane ratings refer to the autoignition properties of the fuel. The higher the cetane rating, the easier the fuel is to ignite. Typical ratings run from 40-50 with 40 being the minimum. Gold diesel is supposed to have higher cetane than average, 47-48 I think? Higher cetane results in easier starting, reduced combustion noise (because less fuel is injected before ignition occurs) and better fuel economy. Higher lubricity is better for injection pump longevity, of course.

 I'm unable to tell the difference between gold diesel and "regular" as far as running performance. My car does start with a bit less misfiring in the cold on gold diesel, not enough that  would go out of my way to get it though.

[3beejay3]

I figure I get roughly a 5% improvement in fuel mileage when I use Sunoco Gold vs. the 'bunker oil' that is sold in some of the independent stations. I have a 97 Jetta TD. 307,000KM

The key is that you have to run several tanks of Gold thru the car before you start noticing a difference(it must have some cleaning properties or something??)
Where I live Sunoco Gold is price competitive with regular diesel and it's availible on my way to work, so I use it all the time. There have been a couple of times when I have used the regular stuff and I noticed a significant drop in range >50km less per tank.

My results are all very unscientific and there are many factors that affect mileage : tire pressure, driving style& mix, ambient temp. etc.

For the first couple of years I owned my car I consistently got about 47-48 mpg using regular diesel. (normal driving. long trips I got about 49-49.5)
I started using the Gold about two years ago and recently I was getting 50-51 mpg consistently.(my normal driving) On Oct. 29th I was at QuickTD's house and he performed some of his magic on my pump. I just finished my first full tank since then and recorded 52.74 mpg(my normal driving). Bruce said my mileage should go up a bit and this tank looks to have proved him right.

It would be interesting to to do a proper test to see what value really is there, if there is any. My long term results suggest that there is.

There are other sources for premium diesel;
Some GTO stations carry Sunoco Gold. GTO is either owned or supplied by Sunoco.
UPI has Diesel 2000.
I believe Texaco has a 'Premier Diesel' product.(not sure though)
Irving Oil also apparently has a good diesel fuel.

BJ