I saw on a posting a week our so ago where someone had their
oil tested.Got back report of high silica content in oil.They where using a K&N That worried me.I pulled the air cleaner cover on my 1980.SL and saw that the intake plenum was covered with grit.I pulled the K&N and put back the stock filter.I contacted K&N.They told me to check height of filter.It was three tenths to short.I let them know.I have not heard another word.I have used these filters for many years,always with good luck.Not on the SL.I reccomend checking to see if grit is getting by the filter.Michael