I would have to agree that I would love it if B20 was in more locations. Especially when I travel. I hate when I do a safety fill up over a mountain pass with regular diesel, but I'll never drive into a snowy remote area without a full tank of fuel.

The really nice thing would be that as it is more widely used by the diesel community, the pollution levels would drop significantly and perhaps make diesel cars much more attractive to the average consumer. The thing is that with the biodiesel calming the engine, the engines being better designed and more efficient, and the overall longevity, I think there would be good potential to reduce the vast market share that gasoline engines have.

ULSD already has an additive in it to take the place of the the lubricating molecules.
(ii)
Lubricity. Regardless of the fuel sulfur level, ASTM D975 currently requires
lubricity specified as a maximum wear scar diameter of 520 micrometers using the HFRR test
method (ASTM D6079) at a temperature of 60°C. Based on testing conducted on ULSD fuels,
however, fuel injection equipment manufacturers have required that ULSD fuels have a
maximum wear scar diameter of 460 micrometers. EMA recommends that the lubricity
specification be consistent with the fuel injection equipment manufacturers’ recommendation.

The lubricity of ULSD is established under the following test:
[ASTM] IP 450, ISO12156 and ASTM D6079.

Now before we get too crazy here, less than 50% of the fuel tested at point of sale was on spec, and this was BEFORE the new ULSD standard. The lubricants additives happen after the diesel has been pushed through the pipeline to the distribution tank farm. This is where the oil companies all get their oil and put their additive packages into the fuel. In the case of diesel that's going to be either Grade No. 1-D S15 or Grade No. 2-D S15, green dye and a lubricant package, detergents, anti-corrosives and stabilizers etc..etc.. and whatever else CARB (for your state) has decided belongs in diesel .

The way that fuels are mixed up and down your likely to find yourself on either end of the ASTM standard depending on where you buy your fuel and which blend they happen to be into. Currently oil is being mixed for what is called "winter blend". Anyways I'm not gonna get heavy into the intricacies of regional oil engineering, as much as I love the topic I find it good reading for nights where I have insomnia.

B20 is good for increasing lubricity of petrol diesel, but if your gonna "splash mix" this on your own make sure you put the petrol diesel in first and then put the biodiesel in. Unfortunately biodiesel is still too small for it to be considered as a serious fuel additive (only 75 mmg in 2006), and frankly the petroleum industry is not only a little leery of the fuel quality problems that have happened in the past, long term storage stability and the fact that the additives that they have are cheaper than biodiesel and more effective in smaller quantities.

I've heard these lubricity myths before, but I have yet to see any proof that anyone has had any fuel that caused the demise of their vehicle. Both EMA and FIE have been trying to raise the lubricity standard since 2002, but the current test hasn't shown a real need for it. On the one hand FIE is tightening up the tolerances on injector nozzles and they want more, but on the other hand you have the oil industry who saying they can't justify putting more additive in and the added cost of removing the sulphur from the fuel when the current test has the wear within the acceptible limits for [ASTM] IP 450, ISO12156 and ASTM D6079.

Fascinating stuff huh?! Short answer run B20 or any mix thereof because you like the stuff. But as far as the general consensus is concerned their is no evidence that that the current standard established by ASTM D975 is inadequate lubrication for any diesel in current production.