Synthetic vs. Conventional - A guy at a party perspective - Saab General Bulletin Board - Saabnet.com
NG900 & OG93 |
Vintage Models |
Clubs & SOC |
Other Cars |
Member Photo Galleries |
Member Directory |
*Buddy Registry |
*Mileage Registry |
What's New |
Photo of the Month |
So a number of years ago I got talking to a PhD chemist at a party who spent most of his career with Mobil developing synthetic oils for diesel trucks. As the only two science types in the room (I an engineer) we meshed well and talked for some time. He told me all about what made synthetics better, I having recently bought a Saab, was all ears. Conventional oils begin as crude oil from the ground and are refined to remove everything you don’t want in there. You do your best to get the unwanted substances out and end up with mostly lubricating oil. You then can add various substances to improve the oil properties, but in the end you have to live with some level of junk that could not be refined out, it is a compromise, and that ultimately limits how the oil performs.
With synthetic, you build the oil from pure elements (I.e. carbon atoms), and add other modifying elements and compounds in just the ratios you want. In other words you synthesize it, building the oil to match a specific design. You don’t have to deal with leftover junk. Synthetics were originally developed for large commercial Diesel engines and aircraft engines, to allow for extended drain intervals. A trucking company wants the trucks on the road making money not in the shop getting oil changed. My PhD pal told me semis doing long distance hauling can typically run 20,000 to 30,000 miles between oil drains if running top quality synthetic.
The main advantage with synthetic oil in a gasoline engine is they take longer to break down, thus you can greatly extend drain intervals, and they can tolerate higher temperatures without forming coke (burnt solids) and sludge. Conventionals will lubricate just as well as synthetics over the short term, the trade off is you need to change them more frequently.
I can see why the guy in the video from Blackstone was not so hot on synthetics, his approach is to buy less expensive conventional oil and change it more often. That certainly works for most people in most cars, and has been proven out. But if your car can run the oil a bit hot in parts of the lube circuit due to inadequate turbo cooling or poor exhaust routing (og 9-3), synthetics will give an advantage. Also consider his perspective in testing, he is measuring the properties of used oil, with a quite random service lives. He is not trying to do controlled experiments to compare one oil type to another after testing in a fixed environment or trying to optimize the design of a synthetic oil through controlled tests and post test analysis. So l totally get why he says to buy an oil that meets API standards and change it every 5,000 miles, that will work for most basic cars out on the road today. But for my 9-3, I am sticking with Mobil 1.
Posts in this Thread:
- SAAB Talk Live: Synthetic Oil vs. Conventional - A lab owner sets us straight, Scott Paterson , Wed, 27 Mar 2019 08:34:411
- Re: SAAB Talk Live: Synthetic Oil vs. Conventional - A lab owner sets us straight, neil dale , Sun, 31 Mar 2019 21:44:211
- Re: Testing vs oil changes, Tom G , Fri, 29 Mar 2019 04:52:51
- OT: Current cost of Synthetics, YowZah!, MI-Roger , Thu, 28 Mar 2019 03:13:43
- Re: OT: Current cost of Synthetics, YowZah!, TG, Fri, 5 Apr 2019 11:14:37
- Re: OT: Current cost of Synthetics, YowZah!, Montana Tom , Thu, 28 Mar 2019 19:41:47
- Re: OT: Current cost of Synthetics, YowZah!, kenS , Thu, 28 Mar 2019 17:08:201
- Re: OT: Current cost of Synthetics, YowZah!, bobc , Thu, 28 Mar 2019 12:44:36
- Re: OT: Current cost of Synthetics, YowZah!, Eiron, Thu, 28 Mar 2019 11:28:13
- Re: OT: Current cost of Synthetics, YowZah!, PGAero , Thu, 28 Mar 2019 11:26:50
- Re: OT: Current cost of Synthetics, YowZah!, JimBlake , Thu, 28 Mar 2019 09:23:27
- Marketing..., Justin VanAbrahams , Thu, 28 Mar 2019 08:19:15
- Synthetic vs. Conventional - A guy at a party perspective, Sondeen , Wed, 27 Mar 2019 19:41:53 <-- Viewing This Message2
- Like gasoline, additives vary nominally, Bloodnose , Wed, 27 Mar 2019 18:41:10
Post a Followup
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
This is a moderated bulletin board - Posting is a privilege, not a right.
Unsolicited commercial postings are not allowed (no spam). Please, no For Sale or Wanted postings, SERIOUSLY.
Classifieds are to be listed in The Saab Network Classifieds pages.
This is a problem solving forum for over 250,000 Saab owners, so expect to see
problems discussed here even though our cars are generally very reliable. This is not an anything goes
type of forum. Saabnet.com has been a moderated forum since 1988. For usage guidelines, see the
Saabnet.com Mission and Purpose Page. Please remember that you are
not anonymous. Site Contact | Site Donations | Other Sites by SP -
Your address is: 126.96.36.199 - Using CCBot/2.0 (https://commoncrawl.org/faq/) - Logged.
Site Members do not see red text instructions, bottom of the page anchor ads, or box ads.
Click here to see all
the Site Membership Benefits!