I'm coming up on 1K miles on my new 3. I've heard various opinions on the best mileage to get the first oil change. Some schools of thought are that there are a lot of metal shavings generated on a brand new engine, with that in mind I've heard to get the oil changed when the car reaches 100 miles.

The other extreme is that no extra effort is needed, and to change the oil for the first time when the manufacturer specifies (7.5K).

I've usually gotten it changed when a new car hits about 1K miles, then every 3K thereafter. That's seemed to work well.

Anyone have some strong opinions one way or another on an "early" oil change for a new engine?

 

Strong opinion here...

Leave your oil alone; the engineers that designed your mill did so with a 7,500 mile OCI in mind, and changing your oil before then will not add even a single mile of life to your engine. To support the above statement, I changed the oil in my (then) new(ish) Mazda3 after 7,512 miles and sent the factory oil out for analysis. The results came back saying that the wear metals were well within tolerance and that the oil still had enough additives left in it to last at least a thousand or two more miles.

 

I agree with shipo on this one, you don't need to change your oil that often. With new mazda 3 cars also, the factory recommends you change your oil only for the first time at 3,000 miles, then after that its every 7500 for the remainder. I had a 2008 mazda 3 for a couple years, and thats what I did. It was perfectly fine. They're built now to go that long.

 

Interesting... Your 2008 Mazda3 recommended an initial 3,000 mile oil change? Hmmm, I wonder if that was a change for 2009 as the schedule for my car (a 2009 Mazda3 i Touring) recommended the first oil change at 7,500 miles. Go figure.

 

yeah ha, they had me have my first one done at 3,000 miles, and then all the rest were done at either 7,500 miles or every 6 months, whichever came first.

 

I did my first @ 7500... but I waited for the full synth until 20k to make sure she was all broken in.
This too seems to be a point of contention with journalists in-the-know these days. Some say that engine need almost no break-in period while others say wait for the break-in @ 10+k.
Mazda claims that no special treatment is needed on these for any amount of mileage, yet I have noticed a definite increase in fuel mileage only recently... @ roughly 45k miles?
I used to see 24-25mpg in the Texas summer heat w/the A/C on full blast all the time. Now I get a minimum of 26, and usually 27-29... and we had a hell of a hot summer this year too!!

 

My last car didn't record its best fuel economy until it had over 145,000 miles on the clock, go figure.

 

Thanks for the input. I'm a pretty low mileage driver so if I change it every 3K that ends up being 2-3 changes per year. I feel like time between changes is a factor too, not just the mileage especially doing a lot of short trips and stop and go. If I changed every 7500 I'd be changing only about once per year. Maybe that's ok, maybe not.

I guess an extra $25 a time or two a year is not money wasted to me and helps me sleep a little better anyway.

 

I've changed my first at 4k and 4k everytime thereafter. I can start to feel the engine get a little sluggish after 3500 or so. But thats just my OCD kicking in, LOL.

I also ran Full synthetic from the first oil change, and have had no problems, though I only have 33k on the clock.