Attention: TDR Forum Junkies 
This from WorkhorseDiesel over on the Cummins Forum - use your own judgement, but it sure seems accurate to me. I thought a few others might like to read and consider it too.
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It's not the sulfur that is responsible for the lubricity in diesel fuel, it's the aromatic hydrocarbons that are already there when the diesel is first refined. When the refinery is using high heat to strip the sulfur from the diesel, a large part of the aromatic hydrocarbons are stripped away as well. One good example of how to "see" the difference that's taken place is to just take a whiff of the new ULSD. The sulfur and aromatic hydrocarbons gave diesel it's noticeable pungent odor. Used to be that if you splashed it on your boots, everybody would know you did well after it happened. Just recently, messing with my fuel system, I got a lot on my hands/arms and unlike in the past, it didn't take too much washing to get the smell off and gone. The smell is now a bit sweeter and not so "diesel-like". Remember not too long ago if you got diesel on your hands it had a greasy/oily feel to it. When you washed your hands, it was hard to get that greasy/oily feeling off. And, if you happen to just WANT to do a quick lubricity test, then you can try the following. Take just a small bit of diesel and "feel" it between your fingers. The bulk of that greasy/oily feeling is gone, as well as the really heavy pungent odor. It's actually a lot cleaner smell now. And, the look, well a quick glance at the fuel going into your tank will show you that the color has changed quite a bit. It used to be a dark orangey/brown color. Now, it's much lighter clear to light yellow color. Looks almost like urine now. If you see a green tint to it, that's usually signs of the additive package but some packages won't tint the fuel so dont' be alarmed if it's not a certain color. When it was still going through it's cutdown time, from May-June, July-October, it was at times almost completely clear like kerosene. It was at this time that using an additive was ABSOLUTELY necessary. At the cutdown time, there were no additive packages being put into those first batches of 25 ppm fuel. It wasn't until the September 1st date, when the fuel reached the terminals that additive packages were put in. Before that, it was common knowledge that refineries were cutting sulfur content and running mix batches through the lines and through the pumps and eventually in our trucks. There was no requirement at that time for the additive requirement. The requirement only applied to (15 ppm) ULSD. The mix batches were not regulated or required to meet the lubricity standard until ULSD was officially at the pumps. I was doing a lot of testing at that time and the majority of the batches I tested with were EXTREMELY harsh. The color was predominantly white/clear almost water-like. Since ULSD has been officially put at the pumps, those batches changed color to a light yellow and the smell of high sulfur diesel is GONE. It's definitely easy to see why the fuel will burn cleaner. It's also easier to see how much damage it can do if it makes it through a terminal without the additive package. From what I remember reading from Cummins, you don't want K1 Kerosene running in your truck WITHOUT at least a quart of lube oil per every 10 gallons used. The tank farm tickets I saw put the lubricity of the ULSD without the additive packages at a lubricity level equal to or lower than Kerosene and in some cases as low as JP-8 jet fuel. That's some of the harshest stuff around and without a doubt NOT what you'd want to run through a sensitive VP44.
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It's not the sulfur that is responsible for the lubricity in diesel fuel, it's the aromatic hydrocarbons that are already there when the diesel is first refined. When the refinery is using high heat to strip the sulfur from the diesel, a large part of the aromatic hydrocarbons are stripped away as well. One good example of how to "see" the difference that's taken place is to just take a whiff of the new ULSD. The sulfur and aromatic hydrocarbons gave diesel it's noticeable pungent odor. Used to be that if you splashed it on your boots, everybody would know you did well after it happened. Just recently, messing with my fuel system, I got a lot on my hands/arms and unlike in the past, it didn't take too much washing to get the smell off and gone. The smell is now a bit sweeter and not so "diesel-like". Remember not too long ago if you got diesel on your hands it had a greasy/oily feel to it. When you washed your hands, it was hard to get that greasy/oily feeling off. And, if you happen to just WANT to do a quick lubricity test, then you can try the following. Take just a small bit of diesel and "feel" it between your fingers. The bulk of that greasy/oily feeling is gone, as well as the really heavy pungent odor. It's actually a lot cleaner smell now. And, the look, well a quick glance at the fuel going into your tank will show you that the color has changed quite a bit. It used to be a dark orangey/brown color. Now, it's much lighter clear to light yellow color. Looks almost like urine now. If you see a green tint to it, that's usually signs of the additive package but some packages won't tint the fuel so dont' be alarmed if it's not a certain color. When it was still going through it's cutdown time, from May-June, July-October, it was at times almost completely clear like kerosene. It was at this time that using an additive was ABSOLUTELY necessary. At the cutdown time, there were no additive packages being put into those first batches of 25 ppm fuel. It wasn't until the September 1st date, when the fuel reached the terminals that additive packages were put in. Before that, it was common knowledge that refineries were cutting sulfur content and running mix batches through the lines and through the pumps and eventually in our trucks. There was no requirement at that time for the additive requirement. The requirement only applied to (15 ppm) ULSD. The mix batches were not regulated or required to meet the lubricity standard until ULSD was officially at the pumps. I was doing a lot of testing at that time and the majority of the batches I tested with were EXTREMELY harsh. The color was predominantly white/clear almost water-like. Since ULSD has been officially put at the pumps, those batches changed color to a light yellow and the smell of high sulfur diesel is GONE. It's definitely easy to see why the fuel will burn cleaner. It's also easier to see how much damage it can do if it makes it through a terminal without the additive package. From what I remember reading from Cummins, you don't want K1 Kerosene running in your truck WITHOUT at least a quart of lube oil per every 10 gallons used. The tank farm tickets I saw put the lubricity of the ULSD without the additive packages at a lubricity level equal to or lower than Kerosene and in some cases as low as JP-8 jet fuel. That's some of the harshest stuff around and without a doubt NOT what you'd want to run through a sensitive VP44.
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