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rossferguson

Different diesel brands = vastly different mileage?

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Hi all,

Does anybody else find that the brand of diesel they buy affects their fuel economy hugely?

I've been tracking my economy via Fuelly, and I've found that buying my diesel at Husky stations makes a massive improvement on my economy - my best tank ever was 4.6L/100km/ and that was running on Husky diesel. I've had Shell's upper-tier diesel, Petro-Canada, Esso, and Chevron, and they've all returned worse fuel economy in that order (with my last tank of Chevron coming in at a jaw-droppingly poor 6.4L/100km!!)

Does anybody else experience this? For what it's worth, I'm in Greater Vancouver.

Thanks!

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I personally haven't found that fuel suppliers change the milage a whole lot. Wind, speed and traffic are the killers. And at this time of the year . . . Winter fuel.

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6.4 is seriously messed up, I have never had such a bad tank, even when driving at a constant 130 km/h. I doubt it's the fuel!

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I do find Husky is noticeably better mileage, but it's not dramatic. 5%-ish? Also I think when the diesel looks a little yellow it's better mileage, when it's greenish it's worse. Even with the same brand the fuel varies depending on a multitude of factors.

6.4 is likely measurement error. The angle of the car when filling up affects how much goes in. If the previous tank was filled with drivers front angled up then this one opposite, you will see about 3-4 litres difference. The worst I've ever seen in a tank I believe was 5.2. Although I do have a few 6+ tanks that I don't believe, preceded or followed by one too good to be true.

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Fuel differences, ie: additives, and whether or not it is winter vs summer..... you might be able to state somewhere in the 2% to 5% difference, everything else being the same.

And that is the kicker, 'was everything else the same'? Right away, different pumps at different stations mean possibly different fuel levels in the car.... even a half litre on a 15 litre fill is 3%.....

There's so many variables to the whole fuel economy game. It's rarely if ever the fuel.

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Thanks for all the replies, folks...I forget that the tiny size of the tank can make a disproportionately-large impact on measuring economy. I'm used to measuring economy in my Grand Caravan and Camaro, and they're much easier to fill consistently and the margin for error is much smaller.

I've tried to keep my driving style consistent across all the tanks, but that's about the only consistent one out of all the variables. And as I'm typing this, the tank (of Husky diesel) I'm currently running on seems to be burning up at a much greater rate than the last one...!

Sometimes when I first start the engine, I'll catch a whiff of diesel smell inside the cabin with all windows / cabrio roof closed. Could the wildly-varying economy - combined with the occasional diesel smell - be indicative of a larger problem?

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I'm very new to all of this having recently purchased a 2005 CDI. Regarding Diesel Fuel, @dmoonen makes a reference to "Winter Fuel" and @smartzuuk mentions "whether or not it is winter vs summer". Can somebody explain this to me. I am also interested to know if there are any additives that should/could be added to Diesel to help get through the Winter. Any suggestions would be greatly appreciated.

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I always thought the large fuel filter fitted on Canadian spec Smart 450 diesels have a built in heater. Without the heater there would be no point outfitting these small engines with such an enormous fuel filter.

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My apologies. I forgot my main point: Engine should perform well in Arctic conditions provided it has a fuel filter heater even when run on summer fuel. Reason: Fuel starvation due to clogged up fuel filter is what mainly causes problems in cold weather. Summer fuel looks like porridge at minus 16. Wax crystals will clog filter. This is avoided when fuel is heated. Therefore no need to worry if the Canadian Cdi's have fuel filter heaters.

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I cant speak for all of them, but I haven't seen a filter heater. Mine has a water sensor jammed down the inside of it, but no heater.

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I'm very new to all of this having recently purchased a 2005 CDI. Regarding Diesel Fuel, @dmoonen makes a reference to "Winter Fuel" and @smartzuuk mentions "whether or not it is winter vs summer". Can somebody explain this to me. I am also interested to know if there are any additives that should/could be added to Diesel to help get through the Winter. Any suggestions would be greatly appreciated.

Your in slightly warmer country than we here in the Montreal area. I've had a diesel since 1987 and have never had a diesel gelling problem. In the winter, Canadian oil suppliers use a different grade of oil than in the summer to prevent gelling. It has a lower BTU content and becauseof this and the lower operating temperature, you're economy will suffer.

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I'm very new to all of this having recently purchased a 2005 CDI. Regarding Diesel Fuel, @dmoonen makes a reference to "Winter Fuel" and @smartzuuk mentions "whether or not it is winter vs summer". Can somebody explain this to me. I am also interested to know if there are any additives that should/could be added to Diesel to help get through the Winter. Any suggestions would be greatly appreciated.

Winter fuel aka arctic stove oil pours at -48 celsius. I forget what the temp was when some ignoramus dropped summer fuel aka furnace oil at our local. Of course it gelled and we had to wait for warmer temps before the car would run again. Our local now posts on the pump when they've gone to 48 pour.

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Just to clarify if any doubt is left:

Winter diesel in areas with a real winter is a different blend. This is done by the refineries and is not something an owner needs to be concerned about except in the case of filling the tank in August and parking it until January.

Just be aware that around the time the leaves fall you'll see a 10-ish% drop in economy which won't come back until you notice how white your legs are.

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Thanks everyone for your responses and explanations. It sounds like this is 1 less thing to worry about when trying to prepare my 1st Smart for winter.

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Summer fuel has more energy in it so you can go further. I don't know how cetane relates to energy amount, but I found from research online:

If Cetane level matters to you :

***Cetane levels by fuel company, from Corporate office emails (2006 Mainly US). Please bear in mind that the current minimum from refiners in North America is 40. Depending on the quality of the oil used as well as refining processes you'll find 40-42 from refiners in the US and Canada. Anything above that has to do with specific companies additive packages. When companies give a minimum value then it will be listed as a single number. When a company gives a range of numbers bear in mind that more often than not you'll probably find the lower number rather than the higher number. If 40 is listed then it generally means that fuel is bought as is from the refiner--if someone messes up and doesn't put in enough additive at the refinery then that can cause major problems for your fuel system. It's recommended therefore that if you get the inexpensive fuel with low cetane you use a cetane booster (PowerService, Lubromoly Cetane booster or Stanadyne are all great choices), or run a little biodiesel in the tank. If something higher than 42 is listed then the retailer adds their own additive package in addition to the standard refinery additive package.
Generally speaking as long as 49 or higher is listed you do not need to worry about adding any additives yourself.

BP (Amoco branded), 51;
Countrymark fuels Diesel-R, 50
Chevron US, 49; or 51 with Techron D labels in select markets
ConocoPhillips through the 76 stations (California) 47-53
PetroCanada, 47-51
BP (Powerblend 47, otherwise 40-42)
Shell, 46;
Sinclair, 46;
Sunoco Gold, 45 (often +1-5) Sunoco regular is usually 40.
Exxon/Mobil, 43-46
Holiday Stations, 40-43
HESS, 40-42, can be up to 45.
Husky, 40 + diesel Max additives raise another 1-3 from there (41-45 max)
Love's: 40
Pilot: 40
Valero: 40
Sheetz: 40
Flying J, 40
Wawa, 40

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Here in BC we have higher Cetane levels and up to 5% biodiesel content

which for me (at least so far) has resulted in a clean burning little machine... :neener:

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I have noticed a change that can only be related to fuel.

 

On one side of the road an Esso, the other an Ultramar.  Filling to the lip on a flat pad (alternating direction of orientation when filling).  Exact same route daily.  Weather conditions within 2 deg of each other with same average relative humidity, same tire pressure, same cargo, same placement of weight, same driving habits (of a grumpy old man) that have arrival to destinations within 3 min of each other repeatedly.  The Ultramar consistently has 510 km to a tank.  The Esso since the temps have dropped has dropped to 422 km.  Both stations have high Diesel consumption with lots of transport trucks and smaller diesel engines.  I am in the midst of changing my thermostat so will let you know how this has changed the results with the engine being up in the proper operating temp range.

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L/100 km is a better measure than "km to tank".  What do the calculations show?

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10 hours ago, Thegorillabear said:

I have noticed a change that can only be related to fuel.

 

On one side of the road an Esso, the other an Ultramar.  Filling to the lip on a flat pad (alternating direction of orientation when filling).  Exact same route daily.  Weather conditions within 2 deg of each other with same average relative humidity, same tire pressure, same cargo, same placement of weight, same driving habits (of a grumpy old man) that have arrival to destinations within 3 min of each other repeatedly.  The Ultramar consistently has 510 km to a tank.  The Esso since the temps have dropped has dropped to 422 km.  Both stations have high Diesel consumption with lots of transport trucks and smaller diesel engines.  I am in the midst of changing my thermostat so will let you know how this has changed the results with the engine being up in the proper operating temp range.

I have also noticed a drop in fuel consumption rates as in number of kms per hundred driven......or cruedly kms per tank fill up, since the colder weather has shown up.  It is definately noticable but not quite at your amounts....I always fill up at the same Ultramar at the same pump, again same thing as you heavy diesel useage for station with heavy trucks filling daily. My driving style hasn't changed much at all either. So I'm putting it down to winter fuel additives or their change in compostion of the fuel for winter useages.  I am still easiy averaging 65 MPGs but nowhere near the 80 I was seeing during the summer months! These are roads clear of snow so not pushing the car through snow to create any resistance in that respect. I also do not idle the car for long before starting off, a few minutes as a rule. I tried to let it sit and idle to get the heat up and it simply didn't generate any, so I drove away. It only takes maybe 5 kms to get heat going through heater core to start warming the cabin. Under soft driving not hard until it gets temp into the engine.  We haven't really had any super cold nights yet so preheating the block hasn't made any differance from a starting stand point either. Starts the same cold or preheated after glow plug light goes out.

I'll keep tabs on fuel and report back when things change again if they do.

 

I will say I'm seriously pissed off that diesel is 20 cents more expensive than gas per litre......not that it makes that much difference on our small tank size cost wise, but the thought we are getting screwed over that much more is eating under my skin!   

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2 hours ago, Willys said:

 

I will say I'm seriously pissed off that diesel is 20 cents more expensive than gas per litre......not that it makes that much difference on our small tank size cost wise, but the thought we are getting screwed over that much more is eating under my skin!   

 

A few weeks ago, Diesel was selling at certain stations in this area for $139.9/L and at the same station, regular gas was selling for $1.05.9 ,,,,,,,,,,,,, GRRRRRRRRRRRRRRRRR

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They are trying to do as England has done, made diesel engines into dirty machines, not wanted  or looked down upon unlike the days pre VW scamming .....before that deisel was the thing to have, now it's looking to be the opposite.

I still don't care as I still pay far less for driving than before the Smart Car craze...lol...

 

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