Thought the following message quoted from another M5 board would be of interest in case this was news to others:
"I took our new M5 in for its 1200-mile service. The service advisor called and let me know that, for 3/00 production and later E39 M5s (and Z8s (-: ), the piston rings have been redesigned to permit the use of 5W-30.
As you can imagine, I was quite surprised by this, so I asked to see the service bulletin. The bulletin is number 11 08 98 as revised in June 2000.
The exact quote is:
'M5 (S62 Engine) produced from 3/00 and all Z8s
The S62 engine incorporates redesigned piston
rings from 3/00 which permit the use of BMW
High-Performance Synthetic Engine Oil 5W-30'
The bulletin continues to emphasize that earlier M5s require the Castrol 10W-60, "to avoid engine damage". It says that it's OK to top up with lower-viscosity oils, but only if the 10W-60 is not available, and that oil consumption will increase if you do so."
"I took our new M5 in for its 1200-mile service. The service advisor called and let me know that, for 3/00 production and later E39 M5s (and Z8s (-: ), the piston rings have been redesigned to permit the use of 5W-30.
As you can imagine, I was quite surprised by this, so I asked to see the service bulletin. The bulletin is number 11 08 98 as revised in June 2000.
The exact quote is:
'M5 (S62 Engine) produced from 3/00 and all Z8s
The S62 engine incorporates redesigned piston
rings from 3/00 which permit the use of BMW
High-Performance Synthetic Engine Oil 5W-30'
The bulletin continues to emphasize that earlier M5s require the Castrol 10W-60, "to avoid engine damage". It says that it's OK to top up with lower-viscosity oils, but only if the 10W-60 is not available, and that oil consumption will increase if you do so."