Okay, you all have me a bit concerned. I have about 270K on my 1990 350SDL and it is all original (timing chain, guides, etc). Runs great, good acceleration and gets about 27MPG. Should I be rushing to my nearest service center to have these parts changed before catastrophic failure? One of my previous MB diesels, a 1979 300SD went 365K miles without anything being replaced. A few years back I had inquired at the local MB dealership and they said there was no replacement schedule for this.

Thanks,
Brian