I was just trying to follow the logic...I assumed that if cP = cSt x s.g., and for 5w30, cP=5300 @ -30C and cSt=6400 @ 40C, then s.g = cP/cST = 5300/6400 = 0.828.
So I guess a used oil analysis is in order...
I'd say weak add pack. the last time my oil stayed that clean was on Super Tech syn, with has weak add pack. GC got dirty real quick.quote:
Originally posted by Ray H:
Another observation (whether or not it's "interesting" is subject to readers' personal interpretation...): I'm nearly 2,600 miles into my first interval with T/A 10w30 and it's still difficult to see the oil film demarcation on the dipstick when I check the level. I'd always subscribed to the belief that oil that "dirties" quickly, is an oil whose detergent/dispersant package was doing its job properly. So, I'm wondering - does this T/A stuff have a weak detergent/dispersant package or is the base oil blend so stable under engine operation that it doesn't tax the detergent/dispersant package with partially oxidized oil molecule fragments to the degree we're accustomed to seeing with a conventional or syn-blend motor oil? Opinions invited. (Just remember what they say about "opinions"...)
The conversion is:
Not an issue with the Product Data Sheet accuracy, this is just Motor Oil Viscosity Properties 101.
Blue, are you sure about that? I thought it was the other way around -- 5W starts out thinner [than a 10W] and VIIs are added to get the 30wt spect at 100c. if the 5W started out thicker, it would always be thicker and they might as well swap bottles with the 10W - unless of course the 5W base has more GIII in it for the low temp spec, which may be the case.
Thanks, Bryan. I guess I didn't go to the "home" page, but the first page of the forums...
I appreciate it, Drew...I tend to get a little wordy sometimes. I hope the 5w30 works well for me as I've already bought a couple dozen quarts!
no reason to be concerned. TA will protect just fine, it just may not be cleaning much, and if you've been dilligent with your oil maintenance then you're prolly not too dirty to begin with at 37k miles. a good test would be to add a few oz of LC20 and see what happens. if the oil turns dark in a few hundred miles then you may have some varnish/deposits in there. also look inside your oil filler cap.
Relax. I left my question open-ended to draw comments. My gut feeling is the ConocoPhillips synthetic blends have both a very good detergent/dispersant package and plenty of oxidation-stable Group III base oil content. There are those who know how to read product data sheet entries and recognize good tribology when they see it, and there are those who judge motor oil strictly on the basis of its selling price. ("If it's cheap, it can't be any good." and, "For just a buck a quart more, you can get a qualtiy motor oil." Talk about blind assumptions!) C'mon, people - those of you who've already gotten used oil analysis on these oils, post 'em! (I've yet to read a post from anyone who's actually used TropArtic Synthetic Blend who couldn't wait to get the stuff out of his engine...
The oil filler cap looks good right now, but I haven't tried the LC...guess that wouldn't hurt. I DID, however, order my Blackstone kit yesterday.
I will probably be sending mine (TA 5w30 Syn Blend) in to Blackstone in a month or so and will promptly post my used oil analysis for feedback...I'm dying to know how it looks!quote:
Originally posted by Ray H:
C'mon, people - those of you who've already gotten used oil analysis on these oils, post 'em! (I've yet to read a post from anyone who's actually used TropArtic Synthetic Blend who couldn't wait to get the stuff out of his engine...)
I wouldn't add anything, you want to know how the oil is doing.quote:
Originally posted by LouDawg:
The oil filler cap looks good right now, but I haven't tried the LC...guess that wouldn't hurt. I DID, however, order my Blackstone kit yesterday.[/QB]
