G8rboy

I just finished with my RX-8's first oil change, and would like to thank everyone that has contributed tips on this forum for making it a smooth one, including:

1. Monster-tightened factory oil filter: The sandpaper inside the filter wrench cap ('F' size) worked great to get a grip on the filter- it loosened with no problem.

2. The use of the universal joint in between two 6" extensions made it easy to work to use a wrench with a filter at that awkward angle.

3. Putting a diaper around the base of the filter mount- something I learned from the Miata guys worked great to contain the oil that spilled from removing the old filter, although there wasn't much to catch.

4. I'm trying the Mobil1 110 filter (instead of the smaller 108) to get a little more filtering protection. It's closer to the size of the factory installed filter than the tiny replacement filter that Mazda recommends. Seeing that it's vertically mounted, it's tough to do my usual oil pre-fill, but I still managed to get several ounces of oil absorbed into the filter by leaving it set long enough.

Now for an interesting observation. I always floor-jacked my Miata up on both sides, but higher on the side opposite the drain to increase drainage. The RX-8 is just high enough that I could have slipped the drain pan under there and manipulated the wrench to get the drain plug out, but the front splash guards would have made it pretty tough. So I decided to jack it up on just the drivers side, just enough to get a jackstand under it, and see if I could get some extra oil to drain from the driver's side oil cooler, not to mention making it much easier to crawl under the car and look around a bit.

I was surprised how much that helped - since the official oil change capacity was supposed to be around 3.7Qts, I anticipated adding 4 quarts or so with the gravity enhancement. By the time I was done with my post-change test drive allowing the oil to fill the filter and other passages that might have emptied out, I have now added a total of 5.25 quarts to get it to the full line. That is a huge improvement over the 3.7 quarts I would have had without the jacking, so I highly recommend it.

racerdave

Good stuff! Thanks for sharing. I also believe in priming the filter too.

RX8_GT

Similar to my first change at 2500 miles - but used Rhino ramps with great success. Quick and not dirty. Refill was just a t 4 quarts to the full line.

John

PS This year with my cars under warranty - I've started to document any 'home' work by a dated digital picture of the odometer - simply note the work in a notebook and on the back of the photo with the oil information. I even staple part of the filter box to it. Plan on buying 10 year warranty - via dealer - before the 47 month or 20000 mile limit.

G8rboy

Update- I haven't gone anywhere since my oil change, but
I've now added 5.5 qts once the oil level settled.

Foureagles

G8r':

Thanks for the post. What you describe is pretty much as I've been doing it on My Dear Wife's 8, and I get 5.0 qt changes that way. I may get a bit more aggressive with the "tilt to drain" at the 10k change (skyhook maybe?), as that's when it's getting full synthetic.

{{{{

starbucks

Interesting.

So no danger of "overfilling" at 5.5 qts when official cap is 3.7?

havyn

i was wondering this as well...

guy321

There is always a danger, but in this case, they are draining 5.5 qts because of the tilting, instead of having the car flat. So they would not overfill. You should probably add 3 qts, then check your level before adding anymore.

G8rboy

Yes- this is exactly what I did... started with adding 3qts, checked the level, then 3.5qts, checked the level, 4qts, checked the level, etc. Important Note=>Be sure you bring the car down from the jackstand before you add oil back in though- since the dipstick is on the "high side" and would be on the 'shallow' side of the pan, I think you could overfill if you kept adding oil while jacked up using the dipstick for a reference.

Anyway, the official capacity is more on the order of 7 quarts (if you have both oil coolers, i.e. US Spec 6 speed MT). The 3.7 quarts is actually a 'replacement capacity' since that's about all that will drain if the car is level. This is really scary to me- you're effectively changing half of the oil (or more realistically diluting half of your dirty oil with clean oil) if you do it on a level surface. On Mazda's recommended oil change interval of 5k or 7k miles, you're really running a long time on, at best, half-clean oil.

RX8_GT

I wonder if jacking up driver's side - draining - then lowering that side and then jacking up passenger side would get even more oil out.

Think I'll try that.

John

G8rboy

I was thinking about that myself- with a floorjack it only takes an extra minute to lower one side and raise the other. I'll try it in a couple months.

Post how much you get out doing that- we can have a contest for most oiled drained during a change : )

RX8_GT

I'm going to try it tonight - nothing to do for a couple of hours. Not due for a oil change but what the hell.

John

RX8_GT

Just finished - got just over a quart by jacking up driver's side - but nothing of note by then jacking up passenger's side only. Even after leveling car.

At end - measured about 5 quarts total. Your results may vary - as they say.

John

G8rboy

Hey Ted- good to see you on the '8 list. Have you started "adding lightness" to your wife's new car? That ignition key is pretty solid