Hi everyone new to site. Just a question about the oil in my rx8. Iv only owned my rx8 for about 6months now and I have all ways used Mazda own oil for the rx8. But it's expensive and Mazda close before I get home from work. So I have been looking into different oil. I went to halfords and look up what oil they say to use and they are saying to use 5w 30 semi synthetic and the mobile1 web site say to use full synthetic and Mazda say use mineral oil. Now to my understanding any synthetic oil when burnt will leave a film witch wil cause engine wear. So my question is why are they all saying different things and what's best for my rx8? Any advise would be great. Thanks.

 

Any good name brand oil rated 5w30 will be fine for use in the UK.

Old synths were different, and formulated from alcohols or amines, modern synths are just like dinosaur juice.

 

Now I'm confused. My manual for my 2005 rx-8 says to use 5w-20. any thought on this?

 

The plot thickens...

 

Loved the discription
Now define Dinosaur juice

 

This is funny indeed. Of course, it's okay to use it...don't worry. Mazda won't lie to the consumers on what to use and what not to use, c'mon people...wake up and smell the fresh brewed coffee, lol

 

My manual for my 2005 rx-8 says to use 5w-20.

That's cos you're in Kalifornia and he's in Halfords (the national car-bits store of England) and the UK manual says 5w30 weight oil, nobody knows why, never a miss-communication.

 

Stealth is all over the oil threads today.

Not even giving me a chance to say............


"No more oil threads, search for Christ's sake!"

 

If "English" is different on the two sides of the Atlantic, why shouldn't the proper oil also be different?

Ken

 

^....................oh, that'll help the situation.......thanks alot!

 

Thanks for the comments so it will be ok to use synthetic oil in my rx8? Any advise on what to use? And someone did tell me about using 5w20 so il ask Mazda and they told me that it because we have colder weather over here so can't run thin oil in winter but not sure how true that is.

 

that doesn't make sense fyi ...

colder would be best with thinner
hotter would be best with heavier

5w-20 was used to balance fuel efficiency and emissions across the US

All other nations use 5w-30 as it is more balanced. If you live on south, south/west coast, you can go heavier, 10w-40 is popular on these forums. If you are more north, stick with 5w-30 as it is more well rounded for all seasons.

Any solid synthetic will do. Redline is the most popular here, while royal purple has always been a selection of rotor-heads. Myth was to stay away from Mobil1, but that has since been squashed.

Even my statement above of "thinner vs heavier" is in theory not correct, as the true comparison would be that colder requires a less viscous oil at colder temps, while hotter requires more viscous at higher temps. Remember not all 5w's are equal so thats why there is debate there.

Sounds like you are in a cold region. Snag a bottle of 5w-30 dino and call it a day...save yourself some money and change oil frequently.

 

Thanks for the advice. I live in the south but I work in London and I spend some time in Scotland so I do alot of driving al over the UK. So I think I'm goin to try redline as there seems to be alot of people useing it and it's not to hard to get hold of.

 

I don't need to wake up and smell the coffee. what i need is someone who has a clue could tell me what would be best for my vehicle. auto makers tend to put all eggs in one basket. I live in palm springs ca. in the summer the temp can get as high as 118 degrees and in the summer only gets as low as possibly 45 (bad day) to 55 60 on a good day. Would someone who is serious about helping others please give me your thoughts on this. Thanks much.

 

just use whats recommended on the manual.
5w20 is what I am using.
in fact the oil temp on the rx8 never goes above 230F because of the oil cooler.

 

https://www.rx8club.com/series-i-tech-garage-22/using-oil-other-than-5w20-175160/

Scroll down a bit and theres a pic of a nice chart in the manual for choosing your oil. Personally I went with 10w40 after searching and reading a ton of crap and opinions on this forum. I'm in vegas and it gets very hot during the summer. Don't take my advice on the oil though, choose after you read a lot of info and make up your own mind.

 

Grab a dino 10w-30 or even 10w-40 for cali, change oil every 3k, end of story.

 

Castrol GTX 10w-40 in SoCal (5w-30 in cooler climes).

5w-20 is just a fleet fuel efficiency rating thing. Jeep, Ford, et al do similar for their 4-cycl vehicles to help average out their gas guzzlers.

Wow, there hasn't been a "best oil" thread in a couple months (how many in 7 years???).

 

there is no confusion use ester based synthetic oil, it leaves the least amount of deposits when burned:



one more:
Our test simulates high temperature piston deposit formulation which reduces engine efficiency. The test oil is heated to 285°C and directed onto a rapidly spinning (2500rpm) aluminum disc which is heated to 330°C. This test lasted 3 hours. At the end of the test, we assigned the oil a cleanliness rating out of 100.

 

Very good info! Quick and easy ahha

 

Ugh ... not gunna really get into this debate, but the above image really means nothing. Did you expect the mobil1 to do worse than the "market general fully synthetic" let alone have them show you a graphic that shows their product ranking less than a passing grade?? Just an fyi, if you want some solid proof on what oils are best for the renesis, hit up the oil results thread that we have here for some third party (blackstone) reports.

Like i stated before, the average joe needs nothing more than a quality dino (like the previously mentioned Castrol GTX) at a proven weight for their environment (in this case a 1030 or 1040) and to change their oil every 3000 miles. If you dont want to be an average joe, there are plenty of threads on this website that will help educate you a bit more in depth on what oils are good and why.

 

Castrol GTX 10w30/40 for summer and 5w30 winter on germany

 

Average Joe is also advised to change his oil every 12,500 MILES.

...so Average Joe better not be using some crappy dino 10w30.

Dino-based 10w30 is the worst oil on the market.



Source - http://www.mazda.co.uk/owning/Mazda-...vice-schedule/

 

The takeaway(mobil 1 marketing message aside) from 2nd image is that there are significantly smaller deposits with syn oil vs semi-syn oil, obviously mineral will be even worse.

Average Joe will have to seafoam the crap out the car very often if peak performance and long life of rotary engine is desired or hope that Mazda extended engine warranty will give average Joe a second chance. But in my book prevention is always better strategy..

 

Totally agree guys, unfortunately, only average joe's tend to create threads on topics that have been discussed, beaten, rehashed, and beaten again.