I too am thinking of changing out the plugs on our '99 SL500, all 16 of them. While using OEM Bosch or Beru is a given. Which one, from Pelican's parts catalog? Per the owner's manual, the car takes either Bosch F8DPER or Beru 14 FGH DPUR. We just got this car last June and I just pulled one of the plugs and what is in there now is the Bosch F8 DPER, which is not listed in the online catalog. The Beru is listed, but the picture shows it to be an iridium plug. As a matter of fact just about every picture of a plug in the Pelican catalog is an iridium plug, which is clearly not what the car calls for.

Also, at what mile mark are supposed to replace the plugs? I have the owners manual, but am missing the maintenance schedule book.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member