Cumulative Synthetic Oil Discussion
#1927
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Hey,
I just got my 05 Rx8 shinka. Currently the car has 51K on it, seems to be running fine. I'm looking into changing oil soon but have run into the synthetic vs non problem. I haven't read enough post on this thread to get a "real" answer (because no one really has one) BUT maybe someone savvy will be able to answer this...
lots of people run synth, lots of people don't... so at what mileage have people blown their engines? did they use synth or regular? any trend...?
thanks and hopefully someone has some insight.
I just got my 05 Rx8 shinka. Currently the car has 51K on it, seems to be running fine. I'm looking into changing oil soon but have run into the synthetic vs non problem. I haven't read enough post on this thread to get a "real" answer (because no one really has one) BUT maybe someone savvy will be able to answer this...
lots of people run synth, lots of people don't... so at what mileage have people blown their engines? did they use synth or regular? any trend...?
thanks and hopefully someone has some insight.
i dunno if anyone answered this for you or if you have already found out but from looking around ive learned that you DO NOT USE SYNTHETIC OIL. Mazda warns against this and even will decline engine warranty if you use synthetics. This is because most synthetic oils are designed to reduce oil "burn-off" and since the rotary engine uses oil injection into the combustion chambers you NEED the oil to burn-off as cleanly as possible.
as i said this is what ive learned from looking around online, i dunno much about cars but im buying my 1st car ever here in the next two weeks (2004 rx8) so im trying to learn as much as possible
Last edited by Cody Saint Peltier; 07-18-2012 at 11:24 AM.
#1931
Out of NYC
iTrader: (1)
i dunno if anyone answered this for you or if you have already found out but from looking around ive learned that you DO NOT USE SYNTHETIC OIL. Mazda warns against this and even will decline engine warranty if you use synthetics. This is because most synthetic oils are designed to reduce oil "burn-off" and since the rotary engine uses oil injection into the combustion chambers you NEED the oil to burn-off as cleanly as possible.
as i said this is what ive learned from looking around online, i dunno much about cars but im buying my 1st car ever here in the next two weeks (2004 rx8) so im trying to learn as much as possible
as i said this is what ive learned from looking around online, i dunno much about cars but im buying my 1st car ever here in the next two weeks (2004 rx8) so im trying to learn as much as possible
No Synthetic? Eat this. oh my god mazda is not selling 5w20? no fuxking way !!!
![](https://www.rx8club.com/attachments/series-i-tech-garage-22/187211d1342639792-cumulative-synthetic-oil-discussion-synthe-renesis.jpg)
and Knight Sports, before you said anything bad about them, they are the ONLY company who has their car displayed at a MAZDA JAPAN Showroom, and using THEIR oil does NOT VOID Car's Warranty in Japan. and people from Knight Sports knows Rotary Engine better than most "smart asses" in NA who talks crap about Synthetic Oil.
![](https://www.rx8club.com/attachments/series-i-tech-garage-22/187212d1342639792-cumulative-synthetic-oil-discussion-oil_5w30_4l_2.jpg)
Last pic, is from me to you.
![](https://www.rx8club.com/attachments/series-i-tech-garage-22/187213d1342639788-cumulative-synthetic-oil-discussion-chill.jpg)
Last edited by nycgps; 07-19-2012 at 09:12 AM.
#1932
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Cody,
If you actually read Mazda's official oil statements, their statement is not one saying "do not use it", it's a statement of "we have not tested, and therefore we can not provide an active recommendation for people to use it."
It's a very critical difference that is often misunderstood. The warranties that get denied because of synthetic use are dealerships who make this same misunderstanding. They are human too after all. If challenged legally, these dealerships would not be able to continue denying warranty due to synthetic. The only times the deny is successful is because the owner rolls over and gives in without a fight.
If you actually read Mazda's official oil statements, their statement is not one saying "do not use it", it's a statement of "we have not tested, and therefore we can not provide an active recommendation for people to use it."
It's a very critical difference that is often misunderstood. The warranties that get denied because of synthetic use are dealerships who make this same misunderstanding. They are human too after all. If challenged legally, these dealerships would not be able to continue denying warranty due to synthetic. The only times the deny is successful is because the owner rolls over and gives in without a fight.
#1934
Out of NYC
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Cody,
If you actually read Mazda's official oil statements, their statement is not one saying "do not use it", it's a statement of "we have not tested, and therefore we can not provide an active recommendation for people to use it."
It's a very critical difference that is often misunderstood. The warranties that get denied because of synthetic use are dealerships who make this same misunderstanding. They are human too after all. If challenged legally, these dealerships would not be able to continue denying warranty due to synthetic. The only times the deny is successful is because the owner rolls over and gives in without a fight.
If you actually read Mazda's official oil statements, their statement is not one saying "do not use it", it's a statement of "we have not tested, and therefore we can not provide an active recommendation for people to use it."
It's a very critical difference that is often misunderstood. The warranties that get denied because of synthetic use are dealerships who make this same misunderstanding. They are human too after all. If challenged legally, these dealerships would not be able to continue denying warranty due to synthetic. The only times the deny is successful is because the owner rolls over and gives in without a fight.
but whats funny is most of these people who swear they will follow what mazda "recommended" on the oil, bu they dont follow mazda's "recommended" them to perform all service at an authorized mazda dealer. damn i love double standard
#1935
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i just wanna say that i stated that i didnt know much about cars and was JUST learning i like just made an account on these forums a few days ago =D but thx for showing me some synth oil i can use =D
-saint
-saint
#1937
SARX Legend
iTrader: (46)
It's never too late IMO, bearing wear may already be there depending on how well it was maintained but a good heavy weight synthetic of the right weight will definitely keep any additional bearing wear from happening.
#1938
No respecter of malarkey
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#1939
My research indicates there's a very basic reason never to use mass-market synthetic oils in an RX-8:
Unlike conventional reciprocating piston engines, the Renesis injects oil directly into the combustion chamber in order to properly lube the apex seals. Synthetic oil is engineered NOT to burn off and, in any case, would not leave combustion residues in conventional engines because the oil is not combusted; it just lubricates.
But the oil used by a rotary engine IS combusted, and most synthetic oils leave residues (the unburned anti-burnoff ingredients) when combusted that can foul a rotary's plugs and valves and damage its apex seals.
Debates about superior lubricating properties or thermal breakdown aside, isn't the combustion residue factor the bottom-line reason why Mazda specifies non-synthetic oils for RX-8s (except perhaps for some exotic, specially engineered, non-mass market synthetics)?
Unlike conventional reciprocating piston engines, the Renesis injects oil directly into the combustion chamber in order to properly lube the apex seals. Synthetic oil is engineered NOT to burn off and, in any case, would not leave combustion residues in conventional engines because the oil is not combusted; it just lubricates.
But the oil used by a rotary engine IS combusted, and most synthetic oils leave residues (the unburned anti-burnoff ingredients) when combusted that can foul a rotary's plugs and valves and damage its apex seals.
Debates about superior lubricating properties or thermal breakdown aside, isn't the combustion residue factor the bottom-line reason why Mazda specifies non-synthetic oils for RX-8s (except perhaps for some exotic, specially engineered, non-mass market synthetics)?
Last edited by Ramart; 09-25-2012 at 02:46 AM.
#1940
Zoomin'
iTrader: (8)
My research indicates there's a very basic reason never to use mass-market synthetic oils in an RX-8:
Unlike conventional reciprocating piston engines, the Renesis injects oil directly into the combustion chamber in order to properly lube the apex seals. Synthetic oil is engineered NOT to burn off and, in any case, would not leave combustion residues in conventional engines because the oil is not combusted; it just lubricates.
But the oil used by a rotary engine IS combusted, and most synthetic oils leave residues (the unburned anti-burnoff ingredients) when combusted that can foul a rotary's plugs and valves and damage its apex seals.
Debates about superior lubricating properties or thermal breakdown aside, isn't the combustion residue factor the bottom-line reason why Mazda specifies non-synthetic oils for RX-8s (except perhaps for some exotic, specially engineered, non-mass market synthetics)?
Unlike conventional reciprocating piston engines, the Renesis injects oil directly into the combustion chamber in order to properly lube the apex seals. Synthetic oil is engineered NOT to burn off and, in any case, would not leave combustion residues in conventional engines because the oil is not combusted; it just lubricates.
But the oil used by a rotary engine IS combusted, and most synthetic oils leave residues (the unburned anti-burnoff ingredients) when combusted that can foul a rotary's plugs and valves and damage its apex seals.
Debates about superior lubricating properties or thermal breakdown aside, isn't the combustion residue factor the bottom-line reason why Mazda specifies non-synthetic oils for RX-8s (except perhaps for some exotic, specially engineered, non-mass market synthetics)?
I'll leave you for the lions.
#1941
Exactly what definitive, indisputable post above are you referring to, Emery? Do you have any specific facts you can cite to refute the premise of my question? Or had you noticed that I was asking a question? Do you really believe Mazda's stated reason regarding its purported lack of research on the issue? If so, have you considered that might be a naive belief?
Last edited by Ramart; 09-25-2012 at 02:45 AM.
#1943
Exactly what definitive, indisputable post above are you referring to, Emery? Do you have any specific facts you can cite to refute the premise of my question? Or had you noticed that I was asking a question? Do you really believe Mazda's stated reason regarding its purported lack of research on the issue? If so, have you considered that might be a naive belief?
The short story is that Mobil1 didn't mix and burn with fuel like you said and so did very few other oils. 99% Of the synthetic lubricants out there actually burn and lubricate better than any mineral based oil but since some were known to be dangerous Mazda couldn't legally tell you to use an oil make instead of another.
Synthetic Oils ARE good. /thread.
#1944
The Heavy Metal Scientist
iTrader: (7)
Bse50 he is probably just going to argue Mazda knows best we know nothing, ownership manual is the bible, 5w20 is what we in the US should use in our cars but not in other countries, and I waisted my money on my Idemitsu and Sohn adapter blah blah blah the cycle of oil debate continues.
Last edited by redline86; 09-25-2012 at 03:36 AM.
#1946
Maybe because the dealer doesn't want to stock a different oil for a car it rarely, rarely services? How many scant thousands of RX-8s have been sold in the U.S. in the last 8 or 9 years? How many conventional-engine Mazdas?
#1947
Mazda's Synth-Renesis and the Knight Sport oil would be the "exotic, specially engineered, non-mass market" synthetics I referred to in my original post. Can we perhaps agree that such oils might be the exception to the rule about avoiding ordinary synthetics?
#1948
Time for boost...
iTrader: (24)
Ramart, you're right. Let's just throw away 8 years (and counting) of research and experience and listen to your wise, regurgitated words.
USE ONLY 5W20!! USE ONLY NON-SYN OILS!! Do NOT use any aftermarket parts on your car, because why would Mazda build a car to be modified? SHOP ONLY AT YOUR LOCAL MAZDA DEALER!
I actually buy all my groceries from them. Great people. Tons of rotary knowledge.
USE ONLY 5W20!! USE ONLY NON-SYN OILS!! Do NOT use any aftermarket parts on your car, because why would Mazda build a car to be modified? SHOP ONLY AT YOUR LOCAL MAZDA DEALER!
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
#1949
The reason is very well documented here. Search for a post from rotarygod that tells you EXACTLY why Mazda can't tell you to use synthetic lubricants and why they're actually much better.
The short story is that Mobil1 didn't mix and burn with fuel like you said and so did very few other oils. 99% Of the synthetic lubricants out there actually burn and lubricate better than any mineral based oil but since some were known to be dangerous Mazda couldn't legally tell you to use an oil make instead of another.
Synthetic Oils ARE good. /thread.
The short story is that Mobil1 didn't mix and burn with fuel like you said and so did very few other oils. 99% Of the synthetic lubricants out there actually burn and lubricate better than any mineral based oil but since some were known to be dangerous Mazda couldn't legally tell you to use an oil make instead of another.
Synthetic Oils ARE good. /thread.
#1950
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Ramart,
If you want to gain any traction with that argument, go conduct a burn test of various oils when diluted with gasoline at combustion temperatures and analyst the deposits left behind.
If you want to gain any traction with that argument, go conduct a burn test of various oils when diluted with gasoline at combustion temperatures and analyst the deposits left behind.