Royal Purple 5W-20 or 5W-30(lower mpg). What do you guys recommend!?
#1
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Hey guys, my rx-8 has been running on Castrol Syntec 5W-30 for the past 4000 miles. I had previously changed the oil with regular 5W-20 oil before going the synthetic route. I also chose 5W-30 because I've read online that everywhere else in the world besides the U.S., 5W-30 is recommended for the rx-8 and is better than 5W-20 for this car.
I must say that I have noticed my gas mileage decrease ever since I changed the oil, and im pretty sure its because i put in 5W-30 ? before i was getting 19-20 mpg and now I have been getting 16-20 mpg with mixed driving. I'm gonna do another oil change next week and I'm trying to decide wheter to put in Royal Purple 5W-20 in the car to raise my mpg's, or Royal Purple 5W-30 ?
My theory is that 5W-30 is recommended around the world mainly because of the performance during warm conditions (better heat protection for the engine than 5W-20) both should work the same in cold weather because they are both 5W oils....but since synthetic naturally is way better than mineral oil as far as cold and hot climate perfomance goes...I'm thinking the use of 5W-20 synthetic oil should be just as good if not better than using a 5W-30 mineral oil + id be getting better gas mileage....So once again the question is: Royal Purple 5W-20 or 5W-30?
What do you guys think ? Id appreciate all the advice. Thanks!!
I must say that I have noticed my gas mileage decrease ever since I changed the oil, and im pretty sure its because i put in 5W-30 ? before i was getting 19-20 mpg and now I have been getting 16-20 mpg with mixed driving. I'm gonna do another oil change next week and I'm trying to decide wheter to put in Royal Purple 5W-20 in the car to raise my mpg's, or Royal Purple 5W-30 ?
My theory is that 5W-30 is recommended around the world mainly because of the performance during warm conditions (better heat protection for the engine than 5W-20) both should work the same in cold weather because they are both 5W oils....but since synthetic naturally is way better than mineral oil as far as cold and hot climate perfomance goes...I'm thinking the use of 5W-20 synthetic oil should be just as good if not better than using a 5W-30 mineral oil + id be getting better gas mileage....So once again the question is: Royal Purple 5W-20 or 5W-30?
What do you guys think ? Id appreciate all the advice. Thanks!!
Last edited by CVale127; 04-27-2010 at 10:04 PM. Reason: spelling
#5
there must be a -40 somewhere at least! 20 and even 30's are way too thin when things get hot! The 0w, 5w or even 10w depends on where you are when it gets cold! I always use a 10w-40 now, and it's just fine.... don't really care about the mileage, prefer to save the engine!
Hey guys, my rx-8 has been running on Castrol Syntec 5W-30 for the past 4000 miles. I had previously changed the oil with regular 5W-20 oil before going the synthetic route. I also chose 5W-30 because I've read online that everywhere else in the world besides the U.S., 5W-30 is recommended for the rx-8 and is better than 5W-20 for this car.
I must say that I have noticed my gas mileage decrease ever since I changed the oil, and im pretty sure its because i put in 5W-30 ? before i was getting 19-20 mpg and now I have been getting 16-20 mpg with mixed driving. I'm gonna do another oil change next week and I'm trying to decide wheter to put in Royal Purple 5W-20 in the car to raise my mpg's, or Royal Purple 5W-30 ?
My theory is that 5W-30 is recommended around the world mainly because of the performance during warm conditions (better heat protection for the engine than 5W-20) both should work the same in cold weather because they are both 5W oils....but since synthetic naturally is way better than mineral oil as far as cold and hot climate perfomance goes...I'm thinking the use of 5W-20 synthetic oil should be just as good if not better than using a 5W-30 mineral oil + id be getting better gas mileage....So once again the question is: Royal Purple 5W-20 or 5W-30?
What do you guys think ? Id appreciate all the advice. Thanks!!
I must say that I have noticed my gas mileage decrease ever since I changed the oil, and im pretty sure its because i put in 5W-30 ? before i was getting 19-20 mpg and now I have been getting 16-20 mpg with mixed driving. I'm gonna do another oil change next week and I'm trying to decide wheter to put in Royal Purple 5W-20 in the car to raise my mpg's, or Royal Purple 5W-30 ?
My theory is that 5W-30 is recommended around the world mainly because of the performance during warm conditions (better heat protection for the engine than 5W-20) both should work the same in cold weather because they are both 5W oils....but since synthetic naturally is way better than mineral oil as far as cold and hot climate perfomance goes...I'm thinking the use of 5W-20 synthetic oil should be just as good if not better than using a 5W-30 mineral oil + id be getting better gas mileage....So once again the question is: Royal Purple 5W-20 or 5W-30?
What do you guys think ? Id appreciate all the advice. Thanks!!
#6
there must be a -40 somewhere at least! 20 and even 30's are way too thin when things get hot! The 0w, 5w or even 10w depends on where you are when it gets cold! I always use a 10w-40 now, and it's just fine.... don't really care about the mileage, prefer to save the engine!
The notion of using a summer and winter oil is a myth and a waste of money. Pick an oil that works well for you in the winter and use it all year round.
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there must be a -40 somewhere at least! 20 and even 30's are way too thin when things get hot! The 0w, 5w or even 10w depends on where you are when it gets cold! I always use a 10w-40 now, and it's just fine.... don't really care about the mileage, prefer to save the engine!
2. Quality Synthetic oils (and synthetic in general) don't thin out during high heat as easy as mineral oils do.
#9
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You dont need extremely hot places like AZ or CA or Africa to use heavier oil.
People who said these are usually the people that never have Oil temp gauges installed on their 8.
When you do, you will know what kind of oil temp you're seeing, even when its 20f degrees out.
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You forgot about film strength.
You dont need extremely hot places like AZ or CA or Africa to use heavier oil.
People who said these are usually the people that never have Oil temp gauges installed on their 8.
When you do, you will know what kind of oil temp you're seeing, even when its 20f degrees out.
You dont need extremely hot places like AZ or CA or Africa to use heavier oil.
People who said these are usually the people that never have Oil temp gauges installed on their 8.
When you do, you will know what kind of oil temp you're seeing, even when its 20f degrees out.
Well Royal Purple states that their oils have a high film strength as seen here http://royalpurple.com/rp-performanc...html........so I guess they would deff be a good choice. What kind of oil do you use on your 8 ?
#11
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Well Royal Purple states that their oils have a high film strength as seen here http://royalpurple.com/rp-performanc...html........so I guess they would deff be a good choice. What kind of oil do you use on your 8 ?
Taste good !
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well, I use 20w50, and ppl hate me for that
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#12
I zoom therefore I am.
OMG
stop making threads about OIL!!!!
there are dozen and dozens of threads that have said exactly what everyone has posted here. L2READ...
even my rant here has been done dozens of times by dozens of people.
stop making threads about OIL!!!!
there are dozen and dozens of threads that have said exactly what everyone has posted here. L2READ...
even my rant here has been done dozens of times by dozens of people.
#15
There are various oil threads which are easy to spot because they have about 50+ pages of posts.
#20
#25
Out of NYC
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Hmm, I dunno, I never had a Synthetic peanut oil before. where did ya get them?
![SHOCKED](https://www.rx8club.com/images/smilies/SHOCKED.gif)
I only had some all natural ones that was made from REAL peanut.
when I turn my engine on OMG it smells great !
BTW, you prefer Olga Kurylenko or Megan Fox?
![EEK!](https://www.rx8club.com/images/smilies/eek.gif)
ppl using it for years so I dont see why not.
I left a bottle of 20w50 outside for a day on 20 degrees weather, it thicken up a bit, but nothing really as scary as people thought it would be. of course oil degrades over time, but Synthetic based would be ok for at least 5 K miles.