Synth Oil

[Althalus]

So, went to Wally World and had my oil switched to Synth, gave me Mobil something (can't remember the type, i'll look tomorrow), but on the window sticker (To remind me to change it) it says to change in 3000 miles. wtf? I thought synth was supposed to be like 6k?

[matt_a]

Synthetic oil does last a lot longer than regular oil. Most garages post the mileage reminder at 3,000 miles because it's the old "Gold Standard" and it's easy for the mechanic to do the math. Heck, even with regular oil, most new car owner's manuals will recommend closer to 5,000 miles. Yet when you go to the dealership and get an oil change, most of them will still post the reminder at 3,000. I think it's mostly just an old habit, plus it gives them more business. A full synthetic will last MUCH longer than that. A synthetic blend will too. To change them out at 3K is wasting money, but I still do it. I look at it as a fairly inexpensive insurance policy. If I have a synthetic blend oil in my car and I get lazy (or too busy) and stretch the next oil change out to say around 4K, I don't sweat it because I know I'm still well within the oil's "limits".

[Vahagn23]

they changed mine to AGIP never heard of it, but they say only dealers can get it, and i have to change it in 3k aswell

[pfc369]

i had a golf tdi before. we (tdiclub.com) members did old analysis at 10,000 miles and found the oil is still good. we all agreed to replace every 10,000 miles. with synthetic oil i think it ill be safe up to 6000/7000 miles in our case.

[themadscientist]

synthetic does stay stable longer than regular oil but it can still get dirty and your filter can still clog up. I have used Mobil 1 for over 10 years in all my cars and still change it every 3 months. It's cheap insurance. I would let your motor break in though before switching over to synthetic.

[Rockhound]

...and i have to change it in 3k as well

Well, you don't have to change it in 3k, that's just their suggestion.

Like others have said, 3k is the 'gold standard' for oil changes - primarily it's a number that originated quite a long time ago. Today's engines are far different from those several decades ago, and like someone else mentioned, even on regular oil there's nothing wrong with going over 3k - most manufacturers suggest service intervals well beyond that.

That's not to say that I don't still shoot for 3 to 4k with Mobil 1 - but no doubt service companies aren't going to start endorsing 5k+ intervals at the expense of business.

I did read an article once that described how freshly changed oil was actually "harder" on an engine than worn-in oil. Seemed to be a somewhat 'scientific' theory as I recall - so too frequent changes might be just as bad as too distant.

[themadscientist]

perhaps the polymers need a little break in before they contract and stretch easily?

[Rockhound]

perhaps the polymers need a little break in before they contract and stretch easily?

You're probably right. Maybe even a little 'dirt' helps, too, as the author pointed out that oil color was not a direct indication of its lubrication capacity.