More Than You Ever Wanted to Know About Motor Oil

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More Than You Ever Wanted to Know About Motor Oil

Post by Sabre » Tue Nov 01, 2011 5:22 pm

Choosing the best motor oil is a topic that comes up frequently in discussions between motoheads, whether they are talking about motorcycles or cars. The following article is intended to help you make a choice based on more than the advertizing hype.

Oil companies provide data on their oils most often refered to as "typical inspection data". This is an average of the actual physical and a few common chemical properties of their oils. This information is available to the public through their distributors or by writing or calling the company directly. I have compiled a list of the most popular, premium oils so that a ready comparison can be made. If your favorite oil is not on the list get the data from the distributor and use what I have as a data base.

This article is going to look at six of the most important properties of a motor oil readily availiable to the public: viscosity, viscosity index (VI), flash point, pour point, % sulfated ash, and % zinc.
Great read if you have the time!
Sabre (Julian)
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Re: More Than You Ever Wanted to Know About Motor Oil

Post by drwrx » Wed Nov 02, 2011 8:47 am

Stuff like this is always intriguing but I've always wondered how "real world applicable" they are.

While I'm sure these numbers are sound, does the 186 VI and 478 flash point of the AMSOIL 5W-30 ($10 per quart) make it worth the cost over the 160 VI and 435 flash point of the Valvoline Synthetic ($6 per quart)?

I'm also sure there is some purpose to the level of % sulfated ash measured, but there is really no qualifier as to what it is; "% sulfated ash is how much solid material is left when the oil is reacted with sulfuric acid and burned." OK, but is .85 better or worse than .70 or nothing? I would assume nothing is best, but that is not stated.

Since most of us likely run 5W-30 in our cars it should be reassuring to see that the tested group were all within 10-15% of each other.

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Re: More Than You Ever Wanted to Know About Motor Oil

Post by Raven » Mon Nov 07, 2011 3:01 pm

Boooo, no *W-20 oil reviewed. :(

EDIT: Also, no HTHS ratings? LAAAAAME.

PS: I already know more than you ever wanted to know about oil. :P
All my cars have drum brakes and are sub 200 hp, what am I doing with my life?
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