Date: Mon, 1 Feb 1999 19:48:38 +0100 From: "Simon Watkins" <106374.2647nopsamuserve.com> Subject: Re: how to love my Saab
supersambanopsamejanews.com wrote in message <79424s$li1$1nopsam1.dejanews.com>... >In article <19990130173715.01116.00001222nopsama1.aol.com>, > saab85900nopsamcom (Saab85900) wrote: >> The 0w-, 5W, and 10W- are all 30 at operating temperatures. The lower number >> is an indicator of the ability to perform (pump up) in cold weather. I run my >> Saabs on 0W-30 AMSOIL, and have since it came out. Works better! >> Dick n Falls church, VA >> Using and selling AMSOIL (First in Synthetics) over 21 years >> > >As a scientist I don't understand how this standard works at all. I was under >the impression that the W rating was the absolute viscosity of the oil. By >absolute I mean at some kind of normal engine running temperature and >pressure. If Mobil are now giving the W rating in terms of some concocted >system that is nothing like a standard then my original point still stands. >The mere notion that you can have a standard but you then "modify" it by the >oil's ability to pump up in cold weather is just crazy! I was under the >impression that 0W has the viscosity of water and that the second number >indicates the temperature range. Well it seems that both of these figures are >obviously complete bull shit and I will never trust oil companies again. NJH. > >-----------== Posted via Deja News, The Discussion Network ==---------- >http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own AFAIK, the W refers to the "Winter" rating of the oil - ie, cold weather performance. In a multigrade, the 0W refers to viscosity when cold, the 30 (for instance) refers to the hot performance. The lower the first number, the thinner the oil (and hence easier it flows) in cold weather. The upper number being the viscosity at operating temperature (whatever that might be as a standard). Just my two pennorth... Simon