Mac, because: 1) No xW-30 (or thinner) oil is allowed in any MB engines
2) With synthetics, there is no need for super-thin oils in winter. Even the 15W-50 weight of Mobil-1 will allow better starting than most any xW-30 dino oil. 3) I can't imagine anywhere in the USA where an engine wouldn't cold start with Mobil-1 5W-40 in the crankcase. 4) Thinner oils, IMO, do more for fuel economy than engine longevity. Some folks who did oil analysis noticed wear metals increases significantly with Mobil-1 0W-40 in the crankcase, and the metals went back to 'normal' when the oil was switched back to 5W-40 or 15W-50. YMMV, etc... -Dave M. > ------------------------------ > Date: Wed, 26 Oct 2005 15:17:41 -0400 > From: Steve MacSween <[EMAIL PROTECTED]> > Subject: Re: [MBZ] converting to synthetic oil? > > > [EMAIL PROTECTED] wrote: > > > For an MB diesel use the 5w40. > > Why not 10w30 for winter? > > Mac
