5W30 or 10W30?
01-08-2006 | 05:18 PM
#1
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5W30 or 10W30?
a salesman told me that 10W30 is better for the engine than 5W30. the only reason mazda still recommends 5W30 is some political/business issue but all his service people use 10W30. anybody hear anything like this?
01-08-2006 | 05:27 PM
#2
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anybody have recommendations on brand? is it bad to top off my oil with a different brand than what's already in there? or is it ok as long as they're the same grade?
how often should i keep it topped off? i don't really mind topping it off every time i fill up on gas. but is it bad in any way to always try to keep the level near full? is there such a thing as too often?
how often should i keep it topped off? i don't really mind topping it off every time i fill up on gas. but is it bad in any way to always try to keep the level near full? is there such a thing as too often?
01-08-2006 | 05:30 PM
#3
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From: Smokey Point, WA
Uhhh you mean 5w20 right?
Originally Posted by zeliggusgus
a salesman told me that 10W30 is better for the engine than 5W30. the only reason mazda still recommends 5W30 is some political/business issue but all his service people use 10W30. anybody hear anything like this?
01-09-2006 | 02:25 AM
#5
Rotary only since 1980
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From: Southeast of Seattle
Originally Posted by Ducky
Uhhh you mean 5w20 right?
There's been a bunch of speculation on the forum that the 5W20 was selected in the U.S. to meet EPA requirements and may not be the best choice, especially in some climates.
01-09-2006 | 09:22 AM
#7
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From: Virginia/Maryland
5W-30 will be better during cold starts, but 10w-30 will be better at operating temps because it has less viscosity index modifiers. But most wear and tear occurs during cold starts, so the 5w is what I have been using.
01-09-2006 | 07:06 PM
#8
Hermitage Holdout
Joined: Nov 2003
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From: Greenfield, NH
I have used 5W30 for the entire time I have had my 8 on the road. My dealer has performed all oil changes and always used 5W30 as well. I live in a colder climate area
(NH - USA) so for me that has made the most sense.
(NH - USA) so for me that has made the most sense.
01-10-2006 | 10:35 AM
#9
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Hiya zeliggusgus. Glad to see you researching the RX-8; there are a few really definitive oil threads on this board already. Try this one:
https://www.rx8club.com/series-i-tech-garage-22/rotarygods-rotary-oil-tech-blog-69805/
https://www.rx8club.com/series-i-tech-garage-22/rotarygods-rotary-oil-tech-blog-69805/
01-10-2006 | 10:38 AM
#10
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Also, be cautious of what the salesmen tell you. 
One RX-8 salesman told me my RX-8 didn't have a power steering fluid reservoir because the power steering and brake systems were combined. Obviously, he didn't know the steering was assisted by an electric motor instead of a hydraulic pump (and thanks to him, neither did I until Go48 posted shop page manuals for me on this board).
One RX-8 salesman told me my RX-8 didn't have a power steering fluid reservoir because the power steering and brake systems were combined. Obviously, he didn't know the steering was assisted by an electric motor instead of a hydraulic pump (and thanks to him, neither did I until Go48 posted shop page manuals for me on this board).
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