[QUOTE=Protagonist;1244303]Two problems happening here, both related to the cold. #2 Diesel contains parafin, and will gel at low temperatures (below +17°F). Winterized diesel is a blend of #2 and #1 diesel, and contains less parafin. Pure #1 diesel won't gel until about -35°F.
So, if your temps got down to -10°F, good chance that the diesel gelled. Problem is, when the diesel warms back up, the parafin doesn't necessarily dissolve again and blend back into the fuel. It's a relatively complicated process to un-gel your diesel. Check this forum to see what some diesel owners recommend:
Gelled Fuel? What to do? - Dodge Diesel - Diesel Truck Resource Forums
Got with "Power Service" about their additives after reading their website. I immediately got one of the products to put in the I3500 which is stored indoors at 45-50 degrees during the winter months. This will help stabilize the fuel during the vehicle storage. Took the I3500 out today on a short trip to a state park west of Tulsa to get the additive dispersed through out the fuel system. It was also a good excuse to "get on the road again" and have a nice lunch out in the great outdoors.
The other Power Service product was for use in fuel where temps go below 30F. I put it in my diesel BMW X5. After 4 miles of going home on Friday, my idle got noticeably smoother and reduced the inherent vibration. The other product is for fuel above 30F.
You can get these products at O'Reilly, Advanced Auto and Wallyworld. After my discussion with the engineer at Power Service, I will be recommending their products in my shop. They have the contract to insure Wal Mart trucks fuel storage and overall fuel quality is proper.