5W30 Oil Don't Cut it, Engine Bearing Pics 58K S1 RX-8 from England.
#252
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#253
It amazes me that people refuse to accept that 40-50W is needed to properly protect the bearings in this engine despite the overwhelming evidence to prove it.
Bearings are protected by Hydrodynamic film strength UP UNTIL the oil is squeezed out due to load. Then you better have sufficent ZDDP.
Since engines and oil were invented this scenario remains constant.
Bearings are protected by Hydrodynamic film strength UP UNTIL the oil is squeezed out due to load. Then you better have sufficent ZDDP.
Since engines and oil were invented this scenario remains constant.
#257
Rotary Power!
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this is the first oil change since i bought the car (the guy who i bought it from takes it to a shop to get the oil changed), the guy would use 5w20 castrol gtx. The car has abobut 80k miles on it.
#259
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Then stay with conventional oil Castrol gtx, and try out 20w50. Do not switch to synth as it might cause issues with the seals since the engine has a good number of miles on it already.
#261
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From my understanding, this has only been an issue a long time ago with certain synthetics interacting with certain materials that made up the engine seals. The user should be fine with whateverW-40 or 50 oil. I would suggested an group IV or V synthetics.
#262
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yeah no problem. Since your engine has been running for a long time with conventional you probably have some sort of resdue from the oil along the seals. If you were to switch to a fully synthetic oil, after a couple thousands miles the resdue on the seals would be cleaned off then causing the wear and tear from the seals before to show and get worse.
So its better to just stick with the same type of oil at such a high mileage. If you were below 20k then switching to synthetic would have been ok as the wear and tear hasn't progressed yet.
#263
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#265
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My Mazda owners manual says I can use it, did you know it also says I can use a 20W50..
#266
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I wonder if they only recommend it now since the S2 has the larger pump, and higher pressure regulator. May I propose a toast? Long live the S2 renesis!
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#272
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I thought I saw a post saying the Aussie oil spec was 0w-30 dino. Could you post a scan of the oil spec page from your owner's manual?
Last edited by TZ250; 10-22-2009 at 12:24 AM. Reason: spelling
#273
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Mazda USA used to list a chart out ... but I guess the US customers are too dumb to decide what they need so ... yeah just push a "we recommended this oil, cuz it gives us best cafe numbers, " and call it a day, it lowers support cost so yeah, thats it
S1 has the same chart.