How much oil do I add when "topping off"?
 

I've been an RX-8 owner for a few months, and I've finally reached the time when my oil is getting low.

My question is, how much do I add when topping off? Is there a specific amount? Half a container? A full container?

As a reference, my dipstick looked like this yesterday:

[---|----------------]


The line being where my oil ended, just a half centimeter or so above the minimum line. Clearly it's "fine" for now, but I would like to get it to look like this instead:

[----------------|---]

So, how much do I need to add?

the same as any other car, not above the top line

Just keep adding a little bit at a time, and let it sit for a bit after adding to check the level. It might be between half and a full qt. Just a rough guess but do a bit at a time.

When it's half way between I usually add almost 1 qt - that seems to bring it just to the max. There is no science to this so I'd like to hear other people's experience too.

Interesting thread.

this is interesting.

I have often wondered when I've topped off the oil how much more oil has yet to drain. I am usually good about checking the level but a few times the light has lit in the driveway on the way to work. Are there any real dangers to overfilling? I have seen the dealers overfill, probably so the driver would not have to add oil.

I've heard overfilling is really bad. I can't remember where I read it. I think it was on a thread here somewhere. But I'm under the impression overfilling is real bad.

Sounds like you have an older RX-8. Newer ones have extra markings on the dipstick to give you a better idea of just how much oil has been consumed. You could use the information in the following thread to "calibrate" your dipstick:

https://www.rx8club.com/showthread.p...ight=CALIBRATE

Or, you could just buy a new dipstick from Mazda.

I follow this same principle, mine was 3/4 of the way between MIN and MAX (closer to MAX) @ last check, I added a 1/2 quart and it brought it right to the MAX line.

There is 1.8 quarts between the Low and Full marks on the dip stick. If I saw your dip-stick looking like what you show I would put in a full quart or change the oil if its due. Yes don't over fill it gets oil into your intake!

Just do alittle at a time. After you add oil a lot of times you can pretty much pour in the right amount of oil or damn close. I would rather add oil and check it 5 times then to add to much oil.

[|--------------------] 1.8 quarts low
[-|-------------------] 1.6 quarts low
[-----|---------------] 1 quart low
[------------|--------] 1/2 quart low

Alwaya a mathematcian in the bunch.