When the ambient temps are at and above 100F, a lighter than 50 weight oil would not keep the oil pressure up at idle when the engine was fully warmed up. 15W-50 synthetic was great in the OM61x and OM60x engines I had. So, if the temps get high, you need heavier oil. If the temps get low, you need lighter oil. If they swing to both extremes, you need multi-weight that covers both ends.
On Mon, Mar 18, 2019 at 4:44 PM Curt Raymond via Mercedes < mercedes@okiebenz.com> wrote: > In a 61x engine 0w40 is hard to keep IN the engine. At least it was in my > '83 240D. That car leaked 5x as bad with 0w40. It started more easily but > was costing me an extra quart of oil a week to keep going. 5w40 leaked way > less and started nearly as well. > > I'd say 5w40 is the sweet spot, especially for older engines that see some > cold. At anything above freezing 15w50 is probably fine and provides higher > sheer strength. I don't think its any "better" because engine oil is most > of the time "good enough" and doesn't benefit from being "better". Most of > us don't run in real extreme conditions... > -Curt > > On Monday, March 18, 2019, 5:11:34 PM EDT, Meade Dillon via Mercedes < > mercedes@okiebenz.com> wrote: > > I think ya'll are wrong with this idea that thicker oil is better. Vast > majority of engine wear normally happens immediately after a cold start. > Thick oil makes this worse. Synthetic oil has far better flow > characteristics (see Curt's test of M1 vs. Dino in his freezer from years > ago) and helps in this case. > > Oil is not only a lubricant but also plays a very important roll in cooling > the engine internals, and for cooling you want a high flow rate. Thinner > oil will flow faster, provide better cooling. > > 0W-40 is the best of both worlds, for diesel. I use 0W-30 in SWMBO's > Infiniti gasser motor. That is at over 250k miles and doesn't burn a drop. > > See Bob is the Oil Guy website, read up on the Oil 101 info. > ------------- > Max > Charleston SC > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > -- OK Don *“Travel is fatal to prejudice, bigotry and narrow-mindedness, and many of our people need it sorely on these accounts.”* – Mark Twain "There are three kinds of men: The ones that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." WILL ROGERS, *The Manly Wisdom of Will Rogers* 2013 F150, 18 mpg 2017 Subaru Legacy, 30 mpg 1957 C182A, 12 mpg - but at 150 mph! _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
