ULSD is 15 PPM max on sulfer with LSD is 500 PPM. Some people say there are performance differences but the lubrication quality of the new fuel is what worries most. Removal of the sulfer also removes some of the lubrication quality of diesel. This is why every additive mfg is adding lubricants to their products. Howe's, Stanadyne and Power Service are about the best out there.ray 07 classic;1579029; said:what are the differences, are there any proformance differences?