Joined: Mar 2003
Location: Tulsa, Oklahoma
Okay, I know enough has been said about synthetic oil, but here's a good way to look at it...
I purchase Mobil 1 in a 5 quart container for about $20, so that's $4 a quart. My previous conventional oil was somewhere around $1.50 per quart. Now, the GA16DE requires 3 3/8 quarts of oil, and for estimating purposes I'll round up to 3.5 quarts. On a per-quart basis, an oil change with Mobil 1 costs $14, whereas the conventional oil at $1.50 per quart adds up to $5.25. That's a difference of $8.75 per oil change (excluding filter costs).
So let's say your engine is slightly more efficient while using synthetic oil and is able to squeeze out 1/2 a mile more per gallon (from 30 miles per gallon to 30.5 mpg is about a 1.7% gain in fuel efficiency). Our car has a 13 gallon tank, and for an entire tank of gas, that would correspond to 6.5 more miles driven. Gas is hovering below $2 per gallon in my area, but at $2 a gallon, that would add up to $0.43 saved per 13 gallon period. I change my oil every 3,000 miles, but even if the efficiency gain is extremely small, the less money spent on fuel during those 3,000 miles almost makes up for the $8.75 more I'm spending once every 3,000 mile period*.
*To be exact, during a 3,000 mile period, improving from 30mpg to 30.5mpg would save (assuming $2 per gallon of gas) $3.38. That cuts the extra expense of synthetic oil down to $5.73.
1993 Sentra XE
5 Speed 2 Door
Last edited by Mack; May 28th, 2004 at 04:05 PM.