I think this document is written for the US market in mind. Basically in a nutshell...
LL-1 oils are for high sulfur content fuels - as in USA fuels.
LL-4 oil is for low sulfur content fuels - as in Germany/Europe fuels
Back in the early to mid nineties BMW had a huge problem with the high sulfur fuels in the USA with their V8 engines. The high sulfur caused many BMW V8 engines to loose compression and rough running. It had to do with teh special cylinder coatings - that the high sulur would damage the way the pistons rings would seal against the cylinder wall.
It became so bad that BMW increased the garranty to 10year/100K miles (only for these effected v8 engines) - and had an open "service campaign" (NOT a recall!) for any 530i, 540i, 730i or 740i owner to have their BMW dealer REPLACE their engine will a different engine block deisgn - as to not have future problems with high sulfur in the fuels.
This is what caused BMW to develop special oils for each market.
Dackel
|