I had my car in for a warranty issue and asked them to do my oil change in which I had 10w30. They called and said they wanted to use 5w20.

Am I using the wrong oil?

 

You're not wrong.

Mazda *recommeneded* 5w20, a North America weight spec.

then Most engine failure (plus the latest recall) applies to NA market

I use 5w30 for all year long, next summer im going to swap it to 10w30.

almost 36 K miles, 5w30, no problem.

 

what?

 

hes indirectly saying that he thinks the problem with engine failures is that mazda recommends too light of a grade of oil

 

in general, there is no "right" oil for your car:

the lower the number generally the less friction will be generated and you will get more power and better gas mileage.

The higher the number and you generally have better cooling and better lubrication for people running extreme duty applications or generally lazy people.

 

that being said I'm running 10w40 right now

 

he says "recomendeded" as if mazda has changed their minds on the proper oil for the car. did i miss something or is it still 5w20?

 

Mazda always recommended 5w20, at least for NA market.

For the rest of the world, Mazda says 5w30.

but i still use 5w30, i have yet to have a problem

Seriously you can use whatever you want, if your car never sees freezing point temp, or if its fairly warm, say about 50+ degrees, you can just use 10w30 and u'll be just fine.

staticlag, I cant prove that its 5w20's fault, but there are many reports out there with *data* to show that, engines that use 5w20 has a much higher failure rate than the ones that use 5w30.

Oh well, what do i know

 

When I e-mailed MazdaUSA they did say that higher weights were acceptable in high temperature weather conditions.

 

Manual says use 5w20. non synthetic.

Any oil should work, (and shouldnt' be a warranty issue either) but 5w20 is what is recommended.

I could be making things up, but I thought that there was something about the oil injection system on the early 8's that was calibrated for something other then 5w20, which caused motor failures. Can anyone confirm/deny this?

 

Ok, so I shouldnt have an issue since its winter here? Im in Texas and was running 10w30 because of the heat here in the summers.

I told them to just change the oil with the 5w20 because I was due for a change. So I shouldnt have an issue right?

 

If its never under 50*F you could get away with a straight 30wt oil which would be better than a multi-viscosity oil - all other things being equal(which they never are).



please link them, very interested in reading them. thank you.

 

Bullshit.

 

Actually, debates aside. My manual only says 5w20, and makes no mention of synthetic. I downloaded 05 & 06 manuals a while ago and didn't recall seeing anything about it in them. It wasn't until 2007 that they mentioned anything, and even there I believe it said to avoid it as it "may worsen starting performance"? All of them say 5w20 regardless of temp in the US that I've seen though.

 

Quote - "The higher the number and you generally have better cooling........."

The THINNER the oil the more heat it will remove.

S

 

I just bought rx8 with 42k miles on it.
I have no idea about oil grades, in my last car i was pouring stuff that was in the manual.
I live in CT and it gets below 50F here
So what grade should i use?

 

5w20. Any name brand, API Service SL or better.

Ken

 

Here is a page from the service manual.

 

ok tomorrow i'm using 5w20

 

Hope you have an extended warranty.

 

That's pretty interesting. That's from the on-line manual at myrotarycar.com, right? It makes *all* of us right in our recommendations.

However...the other service manual that's floating around...the pdf version...specifies only 5w20, API SL, ILSAC GF-3. Same as the US owner's manual. Makes only some of us right.

Ken

 

We should all use Canola.

 

This I would like to see. Please post

 

Here's the excerpt. Had to do screen captures on the relevant parts - looks like this pdf edition is protected against copying and printing.

PM'd the url for the manuals - mods will nuke that if I post it.

Ken

 

I'll end up buying castrol 5w30 :P
http://www.triton-import.ru/a_catalo...strol_5w30.jpg