honda606

It's quite alright to be ignorant about a subject but when you try and comment on it you go from ignorant to idiot.

TrueDrezzer

[QUOTE]Originally posted by honda606

Charly

I've been told the following, and it makes sense to me. Whether you use syn or dino, combustion products build up in them at the same rate. Therefore, the the same change interval should be used for both.
Any comments on this?

honda606

Not true at all.

Like Road Rage said above, if you use a quality synthetic you can easily go 10k if not 15k miles per interval.

Personally I am going to run 7,500 intervals when I switch over. 3,000 miles is WAY too soon to be changing a synthetic and all anyone is doing by that is wasting oil and creating more demand for it.

Charly

Which part is not true? That combustion products build up at the same rate? Is there something in syn oils that "neutralizes" these products? I've always used syn oils and assumed the change interval could be doubled, but now I'm not so sure. Is there any definitive proof that the change interval can be lengthened with syn oils without resulting in additional wear?

honda606

[QUOTE]Originally posted by Charly

Charly

Thanks for the link, 606. Looks like they are having the same discussion over there:
http://theoildrop.server101.com/ubb/ultima...ic;f=1;t=004335

honda606

No problem Charly. I've become addicted to that site as of late.

The guys there really know their stuff and they are nice to boot.

cthree

Once every track event. I track my car about every month and changing the oil is something I do after every track event as routine.

Road Rage

You are incorrect. The dirt generated from combustion byproducts and ingested (from the air) does accumulate at the same rate. here is the difference that everyone seems to have missed:
Recall that mineral oils are REFINED. They have all sorts of contaminants in the raw state that must be processed out - aliphactics, asphalts, waxes, etc. This is done with heat and chemistry. When the oil is put into service, the procedure starts to reverse, and gooey substrates of the oil can form.

Synthetic oil does not have this porblem - it is not as self-polluting. This is because it has been engineered molecule by molecule, free of most of the petro byproducts of mineral oil. Synthetic can be mineral-oil based, and severely hydroisomerized oils or hydrotreated oils can even be called "synthetic" in the US, although they are technically GIII oils.

Synoils also generate less self-friction, and run cooler, and can absorb and release heat at a faster rate. This also helps them stand up longer.

The best synoils also have best additives and high TBN's, which are indicators of the ability to stay non-acidic longer, and offer the highest detergency. Synoils are inherently more detergent than mineral based engine oils.

I say again - the real benefit is in performance extremes (hot or cold) and the ability to be used for extended intervals.