Oil viscosity - more difference than I would have thought

[theholycow]

I don't have time to read the whole thing right now but I do want to skim it...

Absent this, play it safe and follow the severe service interval specified in the owners manual. - I disagree with that blanket statement. I would have said to follow the owner's manual, whether you qualify for severe service or regular.

3000 mile myth section: Agreed. Also, that's interesting about those Saturns.

You'll often see claims such as "everyone falls into the severe service category," but these claims are untrue - Agreed.

For example, the U.S. and Canada has fuel with high sulphur levels which can cause more oil contamination. Japanese fuel has very low sulphur levels. Europe is in-between. - Wait, there's sulfur in gasoline? I thought it was only in diesel and was refined out of gasoline.

The dealers also offer a time guarantee, generally that they'll get you in and out in less than 30 minutes or the next oil change is on them. - Around here, a dealer oil change has always meant waiting two or three hours when I've tried it.

SAE30 oil. Some quick-lube places have been known to offer advertised specials that use SAE 30 oil, as opposed to 5W30 or 10W30. - LOL WUT? I've never heard of any shop putting in SAE 30. In fact, I can't even find SAE 30 if I want it, though I haven't tried hard.

5. Selling overpriced, and often low quality, parts such as wiper blades and washer fluid, PCV valves, thermostats, etc. Never let a quick-lube place do any mechanical work on your vehicle.. They do no use journeyman mechanics.

6. Using poor quality filters. You really want to bring your own filter, from the dealer, with you when you go to a quick-lube place. They may take $1 or $2 off the price if you do this but don't count on it.
....ok then. I think even the pimply faced teenagers working there can handle installing wipers, and most filters are fine.

The reason that oil viscosities have gotten thinner is because bearing clearances have become smaller. Using thicker oils will interfere with oil flow and the oil pressure will increase. - Agreed.

Oil Analysis comments throughout: I don't disagree.

Aftermarket Filters - Uhh...he lists AC/Delco and Motorcraft. I thought those were GM and Ford OE.

[bowtieguy]

http://www.consumeraffairs.com/autom...e_dur_oil.html
http://www.oilsludge.com/

like toyota's issues, these failures are likely design flaw related, but better oil could have help avoid them.

[theholycow]

Originally Posted by bowtieguy

like toyota's issues, these failures are likely design flaw related, but better oil could have help avoid them.

That's the best argument I have heard or can think of for exceeding manufacturer's oil product recommendations in common conditions...but it only applies to vehicles known for sludge issues - and vehicles too new to know all recommend synthetic already.