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Oil-Regular or Synthetic

15250 Views 48 Replies 30 Participants Last post by  fun2drive
I'm torn on whether to switch from using regular oil to synthetic. The one advantage I see is less trips in for an oil changes - 3750 miles (severe condition) to 7500 miles. Thoughts, please.
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I have used Mobil 1 since day 1. Believe I get better mileage. Average 27-28 mpg, can get upwards of 31-33 mpg on highway, depending on wind, AC, etc.
I've run both Mobil1 0w-30 Full Synthetic in my 2004 and Conventional 5w-30 (different brands) and have never noticed an MPG difference. Mobil does advertise it as helping fuel economy, but it's probably such a slight difference that you'd have to track it over a long time to notice.
Here is a good link for further discussions: Compulsive Oil Changers Cause More Engine Wear

And for synthetic fans, here is a long article for your reading pleasures:

Yup, that's the extent of my limited knowledge on the guys can read and decide. For me, even in Texas heat, i am sticking to 7500 mile intervals with regular oil.
Hmmm...that's interesting.

When I ran Synthetic, I often found I'd be changing it at around 4000 miles to do it just before the winter (to avoid changing it again in the cold--it would last until spring). So, I decided it was probably pointless to be running synthetic oil (might run it in the winter for the 0w attribute).

I've been sticking to ~4000 mile intervals with conventional oil since I fit some of the definitions of severe service (but not consistently or all the time). Maybe I should push that a little further back.
I may go to 5000 interval after warranty period only because it is easier for my mind to do the math! :D
I reset my "B" trip counter to reflect the oil changes, so no math necessary (until I unplug the battery for some reason--like I did this time around to run a power cable for my under-seat sub).
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