Champa, Don't fix it if it ain't broke. An interval of 2500 miles should keep that engine slick for life. What parts are you replacing anyhow? Castrol is a great lube. Why all this fuss about synthetic anyhow?? It probably causes cancer in laboratory animals. Sometimes it pays to be "oil fashioned"

------------------
Jeff L
1987 300e
1989 300e
1987 BMW 325