Can there be huge differences in Diesel Fuel

[WM-300]

I normally run Mobil Diesel in my 2003 4x4, and get in the high 19's to low 20's MPG. Since Mobil is about 20 miles away, sometimes in a pinch I get Sonoco at a local station. The my MPG is in the high 16's to mid 17's. This has repeated its self for almost 2 years.



Can major brands of diesel by that different ? Or maybe the Sonoco guy is getting really cheap fuel and selling it as Sonoco ?/????? Have any experienced like MPG changes between fuels.



Up here in the Mountains, my only choice is Mobil or Sonoco



WM-300

 

[WStoops]

I use Mobil and Shell, both the same MPG. At Hess the cost is less but so is the mileage, about 2 MPG less. Your mileage may differ. Sorry, could not resist the pun.

 

[Jengle]

My brother used to work at a Mobil station here, and they bought the cheapest fuel around, but were only obligated to buy one tanker full of Mobil to keep the name. Most of the stations, other brands, do the same. Most of the time, the tanker dumping a load has no brand name on it. Every now and then will you see the name brand tanker pulling in. I have tried 47 Cetane to 40 and found no difference in the higher grade stuff, for mileage. At the prices they are charging now, it should all be "Premium" grade diesel.

 

[Gary - K7GLD]

Tests reveal considerable difference in fuel quality from one station to another - or the SAME station at different sampling times...

 

[jsimpson]

I would suggest that it is more likely that the pumps are not calibrated the same. One is giving you less fuel than it says or one is giving you more fuel than it says.

 

[XJSuperman]

I used to fill up at a citgo station religiously for ALL my vehicles gas or diesel.



Still use citgo when I'm on the road but lately when I fill up in town I use the new walmart's station... which is "murphy oil". I see similar mileage at each station (citgo vs walmart)... filled up today with about 50/50 city/hwy and got 19. 2 hand calc. When I've been filling up the last 4 tankfulls I've made them FULL... all the way until the fuel was an inch or so from the top of the tube... this way I know I'm getting a true 'full' tank so I can get a more accurate mileage calculation.

 

[CBrittan]

It is my experience that diesel fuels are purchased by brand retailers from the lowest cost per unit refiner. Transportation to the retailer is a significant cost, so if you know where the closest refiner is to your geographic location, you can be pretty sure that your diesel fuel is coming from that refiner, regardless of the brand name on the pump. Refiners and brand name retailers also exchange or trade fuels so that a refiner close to the retailer supplies other brands, and other refiners closer to their markets supply their retailers, again regardless of fuel branding.



If you look at the fuel you are pumping, you may see that it is clear, or often has a distinct yellowish tint. Your fuel may have been delivered direct to your brand retailer from the refiner, or from a transfer point supplied by a pipeline refined by another company, or from a ship tanker to pipeline, to distribution point, then to your retailer by truck tanker.



The truth is that fuel branding only matters at the pump where brand loyalty matters.



It is far more important to buy your fuel at high volume stations where fuel should be filtered at the pump.

 

[JAmos]

my 2 cents

I know I am a 12valve but I have also noticed big differences in fuel quality. I am in northern colorado and will drive an extra 20+ miles to Johnsons Corner to fill up with their ultra premium diesel. The fuel is suppossed to have an additional 6 cetane "points" in addition to being a premium fuel. I also add a bottle(trippling the dosage) of diesel service quick kleen additive-also + 6 cetane "points" for the reccommended dosage, partly because it will just leak all over my tool box in the truck-partly since more additive seems to make a difference. So to sum up this combination works so much better than other fuels(even with the additive) that I will gladly drive the extra miles to get the results. Cures a lot of sputtering, white smoke, mileage seems about the same. Jordan

 

[Cattletrkr]

Brand does not matter. Bigger staions are better 'cause the fuel most likely isn't old. I've gotten good fuel from all kinds of different stations and bad fuel from a few. No definite pattern to it. Just a thought--If you get bad mileage on one tank and you think it may be because of the fuel, you may wany to change your fuel filter. Bad fuel might also mean dirty fuel. Been there done that.

 

[GFrance]

Depends on where your fuel is comming from. The pipeline I load out of gets diesel from all the majors & unbrandeds, like Tesoro, duke. New West, Tosco just to give you a few. All the diesel at our loading facility is put into several storage tanks that service one end of the loading rack or the other. Depending on who has the best price that day & has product is who I pull off of. That can go to a truck stop, a branded station, or unbranded station. We are not required to put chevron diesel in a chevron station only the gasoline is regulated that way. Thats why all our diesel is put into common storage & who evers numbers I punch into the computer is who the customer gets billed for. Other loading facilities maybe different, like pulling product right at a refinery.

Hope this answers your question.

 

[PJ]

My take on this is the same way I look at gas. My Corvette takes ONLY 92+ octane. Even then, it has to be Chevron, 76, or Shell. If I even think the word ARCO, it pings like crazy. Also the mileage is gone. I have seen that here in Grants Pass Oregon, there is a Chevron Dealer and a Mobil dealer on Hwy 199 within a block of each other. They both get their fuel, gas and diesel from the same supplier. They also are both priced within a cent or so of each other. They have good fuel. BUT... There is a Shell station on the other end of town that gets the same fuel as ARCO. Why? no one is willing to say. I do know that when I was in California and always did the local Pacific Pride, the owner told me that he delivers to many stations and people think they are getting the same quality of fuel as the other station just because they see his tanker unloading at each station. Little did the customer know, each station can request several additives when another just gets the "plain wrap" fuel. Basically, it all comes to, try a station and if they have a high volume of business, chances are, you will be getting good fuel. If you see a station that is 10 or 20 cents less than the avg station, expect that you will get what you pay for.

When on the road, I always look for a high volume truck stop for my diesel. I then feel I have a much better chance of making it to the next dealer without the "water in fuel" light coming on. Just my opinion, for what its worth.

 

[LightmanE300]

High volume is no guarantee of high quality, that is a myth. Diesel fuel quality is influenced by many factors. While most local diesel stations get their fungible #2 diesel from the same terminal, and it is in effect the same fuel, how the fuel is handled in transportation, and the cleanliness/maintenance of the station's tanks are also crucial. You could start with the best fuel possible and put it in 2 dirty trucks and then to a station that sells a lot but never changes its filters or drains the tanks - and get a crappy tank of fuel.



I personally did fuel analysis testing on 3 of my local stations. One was a busy truck stop amoco that has constant diesel traffic (busy station, must have good fuel right??). The other was a local hess that got moderate diesel traffic, and the third was a texaco that got moderate traffic as well. Brace yourselves - the texaco had 3 million ppm of particulate matter under 15microns per gallon. HOWEVER, the busy truck stop Amoco had 21 Million ppm/gal! Over 7 times the dirt per gallon at the busy truck stop. If anyone wants a copy of the fuel analysis reports, PM me and I'll email them to you. Does this mean that all amoco's are dirty and texaco's are clean? Of course not. Most likely the truck stop amoco hollowed out their filters (a common cost cutting practice), and screwed them back on. This way you see the common Cimtek 10 micron nominal filters hanging off the pump, however you don't realize they are empty on the inside. . The only way to truly ensure good fuel is to test and stick with a good station.

 

[TBrennan]

Most likely the truck stop amoco hollowed out their filters (a common cost cutting practice), and screwed them back on. This way you see the common Cimtek 10 micron nominal filters hanging off the pump, however you don't realize they are empty on the inside. . The only way to truly ensure good fuel is to test and stick with a good station.

Hmm. I think I'll take a permanent marker with me next fuel up and put a mark on fuel filter so I can check to see how often it's changed. How often should they be changed, anyone know?

 

[GFrance]

LightmanE300 is right in the respect to how well a station changes out it's filters & if they put any algicide in the tank to keep algae from forming. As far as dirty trucks hauling it, I don't know of any carriers having dirty tanks. I've been hauling fuel for 22yrs & there has never been any algae or any other problems in our tankers. They are internaly inspected & have to pass a vapor recovery test every year & get a sticker from the D. E. Q. (dept. envirormental quality).



PJ the reason your corvette doesn't like the Arco fuel is because Arco refines a sub grade gas then brings it up to octane level with ethenol useually a 10% mix plays heck on older vehicles & fuel inj. systems unles you have been useing it for a long time it will pick up any moisture from your tank & give your system fits & go thru fuel filters.

The Chevron stations in Grants Pass are owened by Colvin Oil Co. & they load at the same facility that I do & I know most of there drivers. Most major stations require that we put their brand in their stations & do random test at the stations testing for their additive to make sure you are not putting in a different brand.

 

[GFrance]

Hmm. I think I'll take a permanent marker with me next fuel up and put a mark on fuel filter so I can check to see how often it's changed. How often should they be changed, anyone know?

We deliver to several Pacific Pride card locks that are high volume to commercial customers on diesel fuel. The filters can go along time & there is no set gallonage or time line for changing them out. If we get complaints of pump running slower then useual they get changed. I just got off the phone to one of our managers & he said depending on the batch of fuel he can go months on filters, then sometimes he's changing them out in a week.

 

[LightmanE300]

I've never heard about dirty tankers to be honest - my point was just that a lot of dirt and moisture can get in the fuel between the refinery and the gas station. Maybe it picks up dirt at the terminal, maybe it's mostly station managers who only change filters when they plug, do not have proper filtering ventilation systems on their tanks, do not periodically drain and clean their tanks, etc.



Since historically diesels have had lower pressure injection systems than we have today, particulate matter in fuel has been less of a concern. Now that we have high pressure injection, people are starting to see the need for finer fuel filters, and cleaner/better fuel. I think this is why most station managers and truck stop owners haven't put much effort into cleaner diesel - they've never needed to.



Tbrennan on filter changes - it's hard to say. Possibly cimtek has a change schedule based on overall gallons that flow through the filter, but I doubt it. Most station managers I've talked to change them when they get complaints of slow flow.



I spoke with the owner of the texaco station that tested so clean. He has a guy/service come out that changes all of his pumps filters and maintains the pumps regularly, I believe monthly. I'm not sure if it's this consistent maintenance or the maintenance relative to his overall gallons, but they have darn clean fuel. In fact the lab commented that it was in the top 5 cleanest fuels they've tested. Too bad it was only 42 cetane and the hess was 49 :--)

 

[JAmos]

cetane defined?

How exactly does cetane affect the burn rate/power/ timing/mileage for our trucks? Cant remember what the cetane rating of the fuel at my "favorite" station is(46?), but should be fairly high overall with the triple shot of additive I use. Jordan

 

[LightmanE300]

Jamos - cetane is a measurement of the ignition quality of the fuel. The higher the cetane, the more completely the fuel will burn - resulting in incrementally better power, mpg, starts, everything.



It's no guarantee that you'll gain the advertised amount of cetane numbers using additives. Without getting too technical, the actual composition of the diesel fuel will make it more or less receptive to improvements with additives.

 

[JPalese]

AMOCO has a "premier" grade of fuel that gives better mileage in our TDI Jetta by 4 mpg. So far i have not seen any difference in mileage on the Cummins between the premier or any other fuel.



Both vehicles are "topped off" during refueling, so the tank-to-tank fuel burn is exact during the mileage calculation.