Hey, being a first time diesel owner I have what might be a stupid question (actually 3 of them)...

1. What is winter blend diesel (how is different)?
2. Why is it used / what are its advantages?
3. How do you know if the diesel you are using is "winter blend"?

Thanks,
gascan

 

It is a blend of #1 & #2 fuel. The blend is different depending on where you are located in the country. The primary benefit is you don't have to run straight #1 in most areas and you will not gel up (frozen fuel). If you are in cold country you are using winter blend.

That said it looks like you live in Texas so you shouldn't have to worry about this unless traveling to high altitudes or further north

Like most fuels, diesel is a mix of hydrocarbons, and the components have different freezing points. For Number 2 diesel, as the ambient temperatures drop toward 0°C (32 F), it begins to cloud, due to the paraffin in the fuel solidifying. As the temperatures drop below 0°C, the molecules combine into solids, large enough to be stopped by the filter. This is known as the gel point, and generally occurs about -9.5 degrees C (15 degrees F ) below the cloud point.

 

Winter blend is #2 diesel with an equal or more mixture of #1 diesel which has less BTU (less energy) and a lower temperature cloud and gel point. I think TyWebb covered the details well.

There are two ways you can possibly find out (that I know of living in the south).
One is you will notice a 1-3 MPG drop due to the less efficient #1 diesel.
Two is to ask the staff in the station store if they know but sometimes the answer is "Uh, diesel.....what?" so that might not help.

 

Ty - good data on the temps.

Kper - good catch on the lower power (#1 can be 8-12% less on energy content...50/50 blend 4-8%)

Also note that with the advent of "low sulfer" and now "ultra low sulfer" petroleum companies were driven towards a "Hydro-cracking" process in their refineries.

This process breaks down the Hydro-Carbon chains from round doughnuts and long straight chains to very small chains. In essence the parafins/waxes are significantly reduce, the fuel no longer contains the sulfur & parafins - hence less lubricity and harder on the fuel system, and this process does reduce overall energy content (slight)...Another result is lower gel or freezing point.

To be honest I haven't heard of a diesel engine gelling or freezing fuel since the first Bio-Diesel fuels were mandated in Minnesota around 2002-2004?

 

Let me trade places with you in Austin and you will find out LOL

 

Problems occur at higher temps, not lower with ULSD. A good article and explanation of the wax drop out problem here: Stories

The first winter with ULSD, trucks were shut down all over the country with the wax drop out problem. Many were at temperatures that would not have caused a problem before the ULSD.