I've heard many say its "how" long its in the car not how many miles are on it. I've also heard that after a certain period of time oil tends to build up an acid and that is why it is better to change it every three months even if you've only put 1000 miles on it...any of that true? The reason I asked is I switched to synthetic oil about 3.5 months ago and now I'm at 3200 miles and I before I never went past 3k...everyone swears I can go 5k easy and a couple people are saying 7-10k...I will NOT go over 5k but if that whole bit about acid building up is true then I want to change it this week and not wait...let me know either way what you guys/gals would suggest.

 

Not sure about the acid but Ive heard that too. Patman would be the guy to talk to about this since he has done some research on it.

 

I think the 3 month thing is just so you get into the habit of it with periodic changing. I log my miles regularly, and change it every ~3500 miles.

 

You can safely go up to a year on synthetic oil. Some go even longer and their oil analysis results still look ok (I wouldn't go much past 18 months though, that would be really pushing it)

 

So going to 5k (which would put me somewhere in the 6 month range) wouldn't be a problem?

 

No problem whatsoever. I go with 5k intervals in my wife's car, which can often take 7-8 months, and her oil analysis results don't show a problem with this interval.

 

Awesome thanks you're the man...

 

Me..personally, synthetic or not I'm gonna changed that stuff every 3k. I've seen what happens to a motor (my own ) when you slack on oil changes.

 

you mentioned that you switched to synthetic just 3.5 mos ago, based on that i would go ahead and change the oil now since it is probably pretty dirty.... when i first switched to synthetic when i got the car, i changed after 1,000 miles because the weight of the oil, etc was different and really seemed to darken quickly. Now, 3,000 miles when i change it oil looks relatively new...

 

Changing at 5-6k with synthetic is hardly slacking though, many people get 300k+ out of this method.