Synthetic oil price question

I read in another post:

I am curious to know how often other synthetic users change their oil.
While I want to provide maximum protection for the engine, I also want
to avoid *overkill* considering the increase in oil prices.

Why should the rising cost of crude oil cause the price of synthetic
oil to rise?

Although I remember the Cuban sugar embargo. Coke and Pepsi went up,
and so did their diet pops that contained no sugar.

 

Because it is made from crude oil.

I pick up a 5 qt container of Mobil 1 for under $20.00 at WalMart and the
new extended change version is about $22.00.

Richard

 

Because synthetic oil is made from petroleum starting products.

 

I use castrol syntec every 5,000km.

Steve

 

I use Mobil1 every 3,000 miles

 

Mobil One 5W30 every 6,000 miles (~9677 KM).

 

Depends on what your definition of "synthetic oil" is.

Mobil 1 is made from polyalphaolefin (PAO) and polyol and/or dibasic
esters. There was also another ingredient in the discontinued
"Tri-Synthetic" formulas. PAO is made with natural gas as a starting
ingredient. Esters use a different ingredient. This is essentially
making larger polymers out of smaller molecules.

<http://www.officialgazette.com/docs/000/z00043847.shtml>
<http://www.imakenews.com/lng/e_article000052004.cfm>

Most of the US marketers of "synthetic" motor oil are selling "Group
III" (Very Highly Refined) petroleum oil - often blended with esters.
Castrol Syntec is among these. My understand of the process is that
it can only make molecules smaller, although more uniform.

Apparently in Europe, a Group III oil can't be legally marketed as
being a full synthetic oil. Mobil filed an FTC claim in the late
90's and lost.

 

Mobil 1 in both my '92 Dynasty 3.3L and my '99 Caravan 3.0L

I change both at 3000 to 4000 mile intervals.

 

I have used Mobil 1 synthetic since about 1982 and have changed it about
every 8-12,000 miles
in the following vehicles.
1980 Chevy Citation w/2.8 Liter Eng. had 150,000 mi on it before giving it
away (burned no oil)
1986 Nissan 300ZX w/3.0 Liter Eng. has 220,000 mi on orig en(burns 1 qt ever
1200 mi)
1998 Chry T&C w/3.8 Liter Eng. has 115,000 mi on orig eng. (currently has an
oil leak)
The stuff has never let me down and the 300zx had 110,000 miles on it when I
bought it and started using Mobil1.
Greyhound
Tampa FL

 

I use NAPA's *house* brand that is made by Ashland, the makers of
Valvoline. I use it in my 1993 Voyager, and 1998 Stratus. I change at
5,000 - 6,000 miles, which is under the recommended 7,500 miles for
*normal* use.

I used to use Chevron's synthetic, but can no longer find it.

-Kirk Matheson