Or add a liter or two of biodiesel! Even a 2% biodiesel blend in ULSD gets you more lubricity that regular sulfured diesel does. Go up to B5 or B10 and you'll be doing even better.

peace,
sam

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"That f***in' biodiesel is makin' me hungry."

1982 300TD Astral Silver w/ 250k (BIO BNZ)
2001 Aprilia SR50 Corsa Red w/ 5.5k (>100 MPG)

It says on the FAQ that they have added addatives to replace the sulfer,I would guess that they know what there doing, after all they are wearing lab coats.

I don’t think that normally I would go out of my way to find low sulphur fuel, but that cetane rating got my attention.

What’s up with the discrepancy between “east of the rockies” and “west of the rockies” formulation? For the west coast, their datasheets show a “typical cetane index” of 52.5, and a “typical cetane number” of 54. However, the datasheets for the “east of the rockies” product lists a “cetane number minimum” of 45. Big difference - I guess that I should be glad that I’m on the left coast.

They apparently add a lubricity additive to offset the concerns about high wear rates that are inherent with ultra low sulphur content fuels. Shouldn’t be much concern to us here in MBZ land, what with the Bosch pumps being lubricated by the engine oil. Personally, I’ll still toss a bit of power service or redline additive in anyways to help keep everything clean. Of course, I did buy an entire case of “STP diesel sulphur substitute” when I spotted it at the 99-cent store – I figure it can’t hurt (I hope!) & it’s cheap enough at 99 cents; each quart bottle treats “up to 150 gallons”.

It will be interesting to see if I get any better mileage or better running characteristics with this stuff versus the usual low-end swill I’ve been buying at Shell.

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Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.

The EPA requires a minimum cetane number of 40, but in California the CARB requires a minimum of 48, so the "east of the rockies" stuff (which is probably cheaper to produce) wouldn't cut it. Why 54 cetane, I dunno, but I'm not about to question BP's decision .

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'81 300TD Wagon 355k (Miss Diesel)
'83 300SD 180k
'84 500SEL 190k (Parting it out)

Thank you for that clarification – I was not aware that the CARB specified a minimum cetane rating. Perhaps I was wrong in assuming that the stuff I’ve been buying is “low-end swill”…

One other thing I was wondering about: I believe that the cetane rating is solely a measure of propensity to combust. If the energy content (BTU’s) of *any* given diesel fuel is the same, then would it be logical to assume that there would not necessarily be a gain in fuel mileage due to higher cetane numbers. (Or does higher cetane diesel fuel necessarily coincide with higher energy content as well?)

__________________
Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.

Yes cetane rating is the measure of how easily diesel fuel combusts. I don't think higher cetane fuel would result in higher fuel mileage, but it would certainly result in quieter engine operation. 54 cetane fuel would be awesome and it would probably eliminate the combustion knock that my W124 has. I wish I could get my hands on some right now.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL

From Chevron's website.

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85 300CD
83 300TD
78 240D (daughter)

I've have swapped my last couple of tanks full from the normal Exxon here in town with Arco low sulpher available a few miles up the road. I notice a quieter idle with the low sulpher stuff. Maybe it's my imagination, but it also seems to have a bit more zoot. You can sure smell the difference if you spill some on your hands. The low sulpher fuel, smells, well, sort of minty. :p

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'78 300D 310K Maple Yellow / Bamboo
'87 300D 81K Barolo Red / Safron (RIP @ 113K)
2003 E320 34K Pewter/Charcoal
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