Good deisel - Bad deisel

[Buggerific]

Hello boys and girls...

So this may all be in my head but I usually use Caltex fuel because there are so many Caltex servo's around. But this week I got some at Shell and my Rocky seems to be blowing less smoke than it normally does!

Is there any truth to this?

Also for those of you who helped me out before cheers... The gearbox is back in with the 5th gear selector back in place, ha ha. How embarrassing!

[RockyF75]

good to hear. Did you have to drop the box?


There are different grades of diesel but I'm not sure which servo has which. Nick will fire up, I think he works at Caltex and always raves on about how good their diesel is

I've found BP to be marginally better on economy but its always a few cents more than other servo's too.

[HotFourOk]

Diesel is a very grey area when it comes to fuel products... The main factor in diesel is the Cetane rating (much like octane in petrol). This causes a better burn, which leads to more power, increased economy and a quieter ignition.
Add to this the ultra low sulphur stuff, and you have diesel that isn't as good as the old diesel used to be (but better for the greenies).

It is very hard to gain the definitive Cetane information from most suppliers but what I have is:

Shell ULSD - 49
BP Diesel - 46 min, typical 51
Caltex Diesel - 50
Caltex ULSD - 46 (min)
Caltex Vortex Diesel - n/a

My Caltex's 2% Bio - 54.3

BP Ultimate Diesel - Typically BP Ultimate Diesel will have a cetane rating higher than 50, whereas the Australian diesel standard is 46 minimum

I remember reading in some literature that my F78 Rocky requires a minimum Cetane index of 51 for optimum running. No current Australian diesel can guarantee this cetane index, and it is only going to be worse with the newer CRD engines with a low rated product.

At work (Caltex) we have a new biodiesel blend which is only 2% bio. Our Quality Certificate actually says 54.3 Cetane, which is the highest I've seen so far out of the servo's.
Each station should have a certificate on site, so ask next time your there what the Cetane rating of the diesel is, and we can add it to the list.

I've found BP to be the best in my Rocky so far, close to the Bio at work. However, I used Shell a few times, and haven't since, but the Shell near me does have some quality issues from time to time.

[Buggerific]

Ha ha, yeah dropped the box to do a 30sec fix. Then put the box back in!

At least now i know which bolt is which, ha ha.


Fair enough, I might try and see if I can't find out what cetane rating I'm meant to have and see who has what. But I'll also run with shell for a while and see what my fuel economy does...

My last tank from caltex was about 13.9L/100kms which is higher than it normally is but I'm not sure how I was driving the car that week.