1.3_LittersOfFurry

iTrader: (4)

I don't think Mazda recommends 5w20 so the engine can die sooner, they just recommend it to help our cars reach US requirements.




Now does 5w20 kill our engines sooner? That sir is the 9 year old, million dollar question.

Some people use 5w20 and see no issue with out doing anything to help protect their engine. Others pour their heart and soul into protecting their engines just for it to crap out at an early age.

I never used 5w20 before, but I always used 20w50 in my Rx-7's (3 of them) and never seen an engine fail. And after seeing what the oil looks/feels like after 2kmiles I can't ever see myself using anything thinner than 10w40. But that's just my experience. Other peoples experiences will differ.


Here is another of my own personal opinions on why this engine fails so much at random...

It's hand built (with used parts the 2nd go round). Which most would think is better than a machine building it. But a person gets tired, has ruff days, and achieving "perfection" soon turns into "good enough". And it's not like one person builds all the engines, many people do, so one person's "perfection" may be viewed as garbage by standards.

pistonhater

Haha, true.

MarkAngelo

Just wanted to add that the engine will be Turbo'd... Not SC...

MarkAngelo

Do you really experience better fuel economy with that particular oil?

RIWWP

iTrader: (2)

You aren't really reading are you?

Pick a number between 0 and 90 in increments of 5
Add a "w" after it.
Pick a number between 0 and 90 in increments of 10

Pick an advertised type between Dino and Synthetic. (Note, all oils are synthetic. "natural" oil will always be the same weight. Any variation from that base natural weight means it's at least partially synthetic.)

Go find someplace to buy it.


You WON'T get a clear answer here. Simply because there are hundreds of options and you will find SOMEONE to argue for any single one of them.

MarkAngelo

I would go with the lower viscosity at start up and around 40 weight.. I'll start looking for a good 5W40 synthetic oil.

The Rotary tech at the dealer said to not use a heavier weight oil because it can clog the oil jets... lol is that true?

RIWWP

iTrader: (2)

Higher cold weight = slightly longer period of time before the oil system is pressurized at cold startup

Higher warm weight = more effort pushing the oil around, higher oil pressure as your oil pump works harder, thicker film separating parts.

Warm weight doesn't change based on environmental conditions. 40 weight in Arizona summers is the same 40 weight in Canadian winters. The cold weight can definitely matter though. Many people shift their weights throughout the year based on the temps they expect to see. Pretty much just pick the weight you believe is appropriate for the environment you live in.


Oil weight has nothing appreciable to do with internal seal (apex, side) lubrication.

MarkAngelo

If 5W20 is really good viscosity for our engines, then I'll try switching to 5W20 synthetic. I heard that synthetic oil is not going to have sulfur and other chemicals that can be potentially harmful to our engines.

The only reason why I never tried synthetic in the past is because the dealership people kept telling me that synthetic builds a film on the inside of the housing that can be harmful in the long run.. But I never really understood why..

Brettus

iTrader: (2)

Must have missed the bit where that was suggested ?

MarkAngelo

Some person suggested to make my own decision, as this is merely an opinion based topic. However, after educating my self on conventional and synthetic oils, sulfur, chemical content, etc, as well as listen to what is "correct" by factory recommendation, I formulated a conclusion to use 5W20 or 5W30 or 5W40, which ever one is available in Synthetic form. I'm not even going to bring up brands.. This thread will go out of control if we did that. lol

This will be my first time to ever put synthetic oil in a rotary engine... I've always used synthetic in all my boosted vehicles...

I wonder what Turblown uses for their 425 WHP monster RX8...?

Spin9k

Except Mazda sells it own rotary synthetic oil (of a particular type, not all syntheics are ok) in some countries for the RX-8, and hey - if Mazda engineers were so smart after spending "millions" how comes it is that so many of our engines blow up like party poppers on a kid birthday?

"Nobody knows more about rotary engines than Mazda"? True perhaps, so surely they must know they messed up (of course they do) and that's why after 6 yrs of production and ensuing engine failures, they built a US engine remanufacturing plant "Just" for for our "well engineered" failed engines to get rebuilt, there were so many of them lol.

And then they added the 3rd center oil injector for greasing up the center rotor housing in the gen II engine. Opps.... ... just saying .. all's not perfect in Mazda engineering...

RIWWP

iTrader: (2)

"Mazda knew what they were doing" arguments always irk me.

That argument fails to account for engineering decisions that were made AGAINST the engineer's recommendations for reasons that are motivated by political, economic, cost cutting, consumer-friendliness, marketing, emissions regulations, or safety regulations.


For example, injecting dirty 4-stroke crankcase oil. You can bet your *** that the purist engineers working on the rotary wanted to have 2-stroke injection from a different tank, but were overruled, even if for no other reason than the additional consumer complication would have made the car less appealing.

Are-Ex-Eight

iTrader: (1)

Yes. When I switched from 10W40 to Royal Purples 5w20 I gained about 2 mpg fuel economy on the highway on average. It went from 19 to 21.

This is based on data from over 5,000 miles on each grade of oil.

ken-x8

Remember SleepyZ? The guy who said he worked at Mazda's Virginia rebuild plant? He started off painting a picture of careful, high quality work. Towards the end, before he said his management told him to stop posting, he talked about setting personal bests for how quickly he could slap an engine together.

Ken

Spin9k

^ SleepyZ was my guy! Fortunately, when mine popped, he ran out of remans, and I "had to take" a spankin brand new JDM engine instead....

alnielsen

iTrader: (4)

My original engine popped at 13K (08/05) and was replaced by a new JDM engine. That one wasn't any better and popped 11K later (8/06). My present reman has lasted 45K.

Spin9k

^ STOP!!! Now you're just plain depressing me!

GTDave

Did it ever occur to you that maybe the Mazda synth is made specifically to burn inside of an engine leaving little deposit. You have a choice. You can believe someone on the site who doesn't really know anything about rotary engineering or you can trust the manufacturer. Given that choice I would have to trust the manufacturer. It would be interesting to know just how many of those engine failures were caused by people who think they know more than Mazda. How many decided to use an oil that they thought was better than the recommended oil and caused the problems to begin with. The very nature of the car causes many to be driven very hard. There has never been an engine that lasted forever. Hasn't been done yet. I know the rotary is no where near perfect. That is factual information. What I am certain of is Mazda knows far more than any of us could posiibly know. Not only that. They put their money where their mouth is. They warranty the vehicle and lengthened engine warranty to a respectable amount.

GTDave

I don't think the crankcase oil is really dirty. It is continually filtered and it is changed on a schedule. I would think you are correct about injecting a good 2 stroke oil but maybe 2 stroke oil was not the cats meow either. Maybe they found a different kind of oil was needed and decided not to go that route because people would run out and it would only be available at a Mazda dealer. The old adage is "any oil is better than none".

As far as the Mazda knew what they were doing argument. Your reasons still don't change the fact that they still know more about this than anyone here does. Those factors may have something to do with their final decissions but who knows more than them? Do you or I? I doubt it. So use 5W20 or 5W30 depending on what temps you drive in and enjoy the car.

RIWWP

iTrader: (2)

Very valid point.


Now please point out to me where they have shown the sum collection of their knowledge that includes "this is what we wanted to do, but couldn't because emissions controls got in the way" and "this is what we wanted to do, but couldn't because it would be too much of a pain for consumers"


Your point is completely valid, but it does not validate that "the owner's manual is providing the best answer" You would have to have a thesis from the Mazda engineers, laying out every option as well as the reason why each option wasn't chosen.


Since you can't get that, you can not assume that the single selection Mazda made was in-fact the best technical selection.


Edit:
I should also point out that Mazda DID NOT know everything about the 8 when the choices were made in 2002-2003 range (perhaps a bit earlier). That's like saying "Mazda knew the internal oil injection for the center of the apex seals was going to be insufficient, but lets produce it anyway." There is nothing to find flaws like half a million production units racking up the mileage under every environmental, driving behavior, and maintenance behavior possible.

Spin9k

I thought that was exactly what I said about the syn oil and Mazda knowledge of the rotary isn't it???? And obviously Mazda took the failures and made them better (not right). Never said they didn't do right by owners by in large. And sure, some owners kill their cars and go beyond normal use. Also other manuf have problems obviously, sad that it is true.

fuztupnz

iTrader: (4)

What weight oil do you think this is? This is the type of oil discussion we should be having. The current one is well past beating a dead horse.

RIWWP

iTrader: (2)

A reminder of the truth posted as the first reply.

fuztupnz

iTrader: (4)

another possible topic: What kind of oil do they use for oil wresting.

GTDave

No manufacturer of anything is going to say "this is what we wanted to do but couldn't". Not going to happen. Mazda does have a vested financial interest in ensuring your engine gets the lubrication it needs. They back that up with warranty. The want you to buy another Mazda later on. They would not steer you wrong for those 2 reasons alone. Yes they have improved the product. Every manufacturer continues to improve the product as time goes by. Mazda has done that. Unfortunately no company can do better testing than the consumer does. They just can't get 50000 diferent drivers to operate the vehicles for an extended period of time. They learn from real day to day driving and make changes along the way. It dopesn't mean your 2004 is a piece of crap it just means the newer ones are a little better.

We use Crown Vics here at the police. 20 years of the present model. Hundreds of changes and the original one in 92 was a pretty good car. The newer ones are better. If you want the best, you need to buy the very last year of production of any vehicle. Unfortunately you don't know how long that will be for any car. Rotary engines are unique and have some problems. But we knew that when we went looking for one.