The oil subject

[Bill Niles <bniles@schafer-assoc.com>]

This is my two cents concerning the oil issue.

A couple of years ago I was trying to find some good info about
synthetic vs conventional oil. Out on the net I found a series of
documents that gave a very detailed explanation of petroleum based and
synthetic oils. The articles in the thread where all submitted by
engineers of various disciplines. One article in particular hit on a
couple of important points, as follows:
(Please excuse my writing and generalization of the content. It's been a
while since I read the stuff so I'm writing from memory.)

Multi-weight petro-based oils were a good idea however a couple of
things needed to be kept in mind. If the engine temp reached the point
that it "burned" the low (i.e. 10w-30) end than the effectiveness of the
oil as a whole was compromised. If you did use a multi-grade it should
not have more that a 20 point difference, in other words 10-30 is ok but
20-50 is not. A multi-grade that was trying to cover this much ground
was going to be too susceptible to break down.

Synthetic oils on the other had are apparently far more durable. With
synthetics you don't experience the same break down on the low end and
therefore the entire mix as a result of high temperatures. Also, because
of the way they are created you can use as wide a spread as you would
like. At the time I way reading up on the subject Mobil-1 was about to
release a 5w-50 that would be just as durable as a 10w-30. Talk about
covering your bases. I've used this oil and it does not come out of the
bottle like a 50 weight.

Personally I switched to synthetic after reading all the info and
haven't regretted it. In fact I am really pleased with the results. I
live in Montana and during really cold periods like -20 to -30 degrees
the synthetic stays amazingly fluid and therefore doesn't make it any
harder for the car to start. If it's a during the warmer times the car
seems to run very smooth and at a reasonable temp.


Unfortunately I couldn't find the original information but I did find a
couple of sites that had what appears to be good reliable information. 

http://www.cs.earlham.edu/~davel/volvo/faq/oilsfilters.html

http://www.euro.net/TDRS/MINIWEB/syn_oil.html

Bill
'64 Notch