Motor Oil ?????? What kind is best?????
 

I have a 2004 rx-8 and was wondering what the best kind and the best weight of oil to use in its rotary motor.

I would go with a little bit heavier weight being a rotory you don't have to worry about the oil lubing smaller engine parts like locks, keepers, retainers, rocker arms ext. maybe like a 10W30 synthetic blend and depending on the time of the year and temp. quacker state has A good one and price is very reasonable. But if you have the money go with moble 1. also if it is like your first or second oil change add some ZMAX stuff really works.

5W20 is what Mazda recommends per the owner's manual. If its very warm where you are then you might like to use a 5W30 at least, which will still give you the widest temp range for protection. Make sure you find oil with the newer GF-4 rating, I use Castrol GTX but my Mazda dealer uses Mobil. If you plan on going synthetic, a lot of people here swear by Royal Purple motor oil.

it's just motor oil for crying out loud, there is no magic elixir ...

Doesn't mean that their isn't a noticble difference.

Look at all the choices we have for sodas:

Pepsi
Dr. Pepper
Coke
etc...

Just because they are all brown and fizzy doesn't mean they taste the same.

I'd like to see you use a 50W oil in your car and then tell me "It's just motor oil..."

The guy asks for suggestions and suggestions are what he'll get.

Royal Purple is good(for a weekend racer), But I heard it was expencive. Is that true?

:eek: Wow I would like to see someone hard start a rotory with a W50 in the middle of winter. I say it runs for a good 2 min before you get some siurous engine knock and motor goes bye-bye.

never used it myself, like I said earlier some people here in this forum swears by it. The color is even purple!

I think if you really want it a few dollars extra per 2000-3000miles is not too bad.

5 - 30 W Mobile 1 Extended Performance Thats what I use......

Royal Purple is great, I have been running it for 14,000 miles. The first time I changed, I noticed the engine was quiter and reved a bit faster.

Usually you have to order it by the case. Just go on their website and you can see who carries it in your town.

http://www.royalpurple.com/dealers/dealers.html

a 12 quart case usually runs me about $65-70 dollars with tax. I usually can do 2 oil changes with this plus fill ups in between.

Which means its just as expensive as any other brand's full synthethic oil. I kno valvolines full synthetic usually runs in the $5.5-6.0 price range (per quart).

Of course, compared to dino oil or blend at about $1.30 a quart, any synthetic is expensive.

I use Royal Purple 5W20 in all of my cars, rotary and non rotary. You can buy it at O'Reilly's if you have them there. It is about $3.50 or so a quart as compared to say a regular bottle of oil at less than a buck. I also only use Wix oil filters. My cars always run smoother and get slightly better mileage than with conventional oils. $20 more is a small price to pay every few thousand miles for added protection.

ROFL...

So royal purple works as a full synthetic? Is that $70 for 12 quart's? if thats all true I am switching to Royal Purple. we sell the stuff in the shop but I kind of thought it was silly, you know being purple and all, I never looked at the price but we sell it by the quart. I might have to pick up a case.

That's actually pretty expensive compared to what I pay for it. A case of 12 should only be about $45-$50 or so. It's awesome stuff.

Just reading about it on there web site sounds like awsome stuff makes me wonder why I used anything else.

http://www.royalpurple.com/techa/whyrpa.html

My friend Jim has an '02 Z-28. He uses their gear oil in the tranny and the diff and also their motor oil. He swears by it.

Not to take away from anyone's thunder...but reading "data" from the manufacturer site does tend to carry a specific bias. :)

You can do the same thing with redline oils...
http://www.redlineoil.com/why_redline.asp

I use redline 5w-20 myself, due in part to the high HTHS # (3.3), but I also don't have the good fortune to own a rotary engine :(.

According to info on bobistheoilguy.com...the 5w-20 RP oil is closer to a 30 wt, then a 20wt...and stays in grade..much like the redline does. I don't know the RP's HTHS # offhand though. Basically the current tech 20 wt synthetics give you the sheer stability of 30-40 wt oils, with the flow characteristics of a 20 wt.

I use A product called Zmax in the engine, tranny, and gas tank, ever heard of it. works great, but it's not an oil it's just an added lubricant like slick 50. Works great but oil wise I am really considering this Royal Purple. Wonder what would happen if you combind these 2 products?
http://www.zmax.com/

Check out...

http://www.bobistheoilguy.com and search for

FP or LC

http://www.lubecontrol.com

Zmax btw is considered "snake oil" and has a variety of negative posts about its performance. (You can find the rest of the links yourself, I don't feel like posting 20+ more links :) )

http://www.lubereport.com/e_article0...ynqMH,a10YHrMT
http://theoildrop.server101.com/cgi/...=003165#000006
http://theoildrop.server101.com/cgi/...=000674#000000

Amsoil is also a really nice oil. My 2 personal favorites are Royal Purple and Amsoil. I've heard lots of nice things about Redline but have never used it. I believe these are probably the 3 oils to beat. It's a little harder to find Amsoil here but there is a small place at a private airport near me that carries it. You can actually set yourself up as a dealer and get discounts for it. It actually isn't that much oil to do so. If you can get 3 other friends to go in on the deal, you would all have enough oil for a years worth of changes.

This is probably why I use 5W20 RP in my rotaries with no issues whatsoever and love it while others use 5W20 conventional and swear it is too light and breaks down.

Rp........
 

...it's not so expensive, if you buy in BULK! ;)

S

Holy crap. The rest of us are buying it by the pack or case, he's buying it by the keg!!!

Amsoil does make some good oils as well. You just have to ignore alot of the marketing drivel on their sites...I wish they'd clean up their act some.

One of their better oils is the 0w-30 Series 2000, which a good deal of people seem to have good results with.

Also 0w-30 GC (German Castrol) is an excellent oil, but has been discontinued, and will no longer be available in the USA. Its commonly refered to as the "Green Elixer".

http://www.wam.umd.edu/~greghess/gcback.jpg
http://www.wam.umd.edu/~greghess/gcfront.jpg

Has to say made in germany on the back, and have a "red" label. The oil also has a green tinge, to it. (Thus the term, green elixer).

Royal P. or Mobil 1, I like both of these fully synthetic oils, but Mobil has a lot more money when it comes to R&D.......Mobil 1 is the clear winner here, besides no F-1 cars use Royal P.

So I'd say the battle between whether or not to use synthetic in a rotary has been put to bed?

Team Penske, West McLaren Mercedes, Porsche, Mopar Performance, Corvette Racing and an incredible 74 percent of NASCAR drivers trust Mobil 1 technology to protect their racing engines. Mobil 1 Racing 0W-30, specifically designed for exceptional performance and protection in NASCAR engines, is now being made available to consumers.

Features & Benefits
Mobil 1 Racing 0W-30 is a proprietary blend of high-performance synthetic basestocks fortified with SuperSyn anti-wear technology. This advanced protection is engineered to deliver maximum horsepower.


Has boosted levels of anti-wear protection -- well beyond those of ordinary automotive oils -- to help protect engines even during grueling racing applications.
Maximizes power output by reducing internal friction.
Has outstanding shear stability and a robust additive package to help reduce oil breakdown and help extend engine life, even under the most extreme conditions.
Compared to conventional racing oils and higher-viscosity synthetic motor oils, it provides faster flow to critical engine parts at low temperatures
Delivers exceptional high-temperature protection, even at temperatures up to 400 degrees F (204 C)

Applications
Mobil 1 Racing 0W-30 is intended for professional, amateur "weekend" race cars, as well as, modern high-output engines of all kinds. It is ideal for supercharged, turbocharged and high-revving, high-performance engines used in street applications. Note: Mobil 1 Racing 0W-30 is a different formula than Mobil 1 with SuperSyn 0W-30.
Mobil 1 Racing 0W-30 is especially suitable for racing conditions, where conventional oil may not provide adequate protection
Mobil 1 Racing 0W-30 is designed for use by professional, amateur and weekend racers.
Mobil 1 Racing 0W-30 is ideal for high-horsepower, high output engines used in street applications.
Mobil 1 is not recommended for 2-Cycle or aviation engines, unless specifically approved by the manufacturer.






Typical Properties

Mobil 1 Racing 0W-30

SAE Grade 0W-30SAE Grade 0W-30
Viscosity, ASTM D 445
cSt @ 40ºC 56
cSt @ 100ºC 10.3
Viscosity Index, ASTM D 2270 175
Sulfated Ash, wt%, ASTM D 874 1.2
HTHS Viscosity, mPa·s @ 150ºC ASTM D 4683 2.99
Pour Point, ºC, ASTM D 97 -54
Flash Point, ºC, ASTM D 92 234
Density @15º C kg/l, ASTM D 4052 0.851

Mobil 1 0W-40 is the most advanced performance synthetic engine oil designed to provide ultimate cleaning power, wear protection and overall performance. Mobil 1 0W-40, European Car Formula (NA) or Protection Formula (EU), exceeds the requirements of the leading industry and car manufacturers' standards required for newer modern gasoline and diesel powered automobile engines. The Mobil 1 Technology is race proven and the choice of NASCAR racing. Mobil 1 0W-40 is perfect for all types of vehicles anywhere in the world and has the performance reserve to protect when conventional engine oils cannot. It is the first choice at the factory for the some of the world's finest performance vehicles: Mercedes-Benz AMG, Porsche, and Aston Martin.

Features & Benefits
Mobil 1 0W-40 is made with a proprietary blend of ultra high performance synthetic basestocks fortified with Supersyn Technology. Mobil 1 0W-40's wide viscosity range provides unsurpassed levels of protection, fuel savings and the best overall smooth driving experience. Mobil 1 0W-40 keeps engines starting in Arctic extreme cold and cleans deposits, sludge and varnish often formed in high temperature operating conditions. Exceeding most of the global industry standards and the major leading builder requirements is the cornerstone of the performance reserve that lets Mobil 1 0W-40 keep performing well after conventional oils cannot. Key features and benefits include:


Features
Advantages and Potential Benefits
Active cleaning agents Prevents deposits and sludge build-up to enable long and clean engine life
Outstanding thermal and oxidation stability Reduces oil ageing allowing extended drain interval protection
Low oil consumption Less hydrocarbon pollution
Enhanced frictional properties Greater fuel economy
Excellent low temperature capabilities Quick cold weather starting and ultra fast protection
Extended engine and electrical system life
High Viscosity Index and Supersyn Technology Excellent overall lubrication and wear protection performance for all driving styles and conditions

Applications
Mobil 1 0W-40 is recommended for all types of modern vehicles, especially high-performance turbo-charged, supercharged gasoline and diesel multi-valve fuel injected engines found in passenger cars, SUVs, light vans and trucks.
Mobil 1 0W-40 is especially suitable for extreme conditions, where conventional oil often cannot perform.
Mobil 1 is not recommended for 2-Cycle or aviation engines, unless specifically approved by the manufacturer.




Specifications & Approvals

Mobil 1 0W-40 meets or exceeds the following industry specifications:

ACEA A3,B3,B4
API SM,SL,SJ,EC,CF


Mobil 1 0W-40 has the following builder approvals:

BMW LL-01
Daimler Chrysler 229.3/229.5
Opel Long Life Service Fill GM-LL-A-025
Opel Diesel Service Fill GM-LL-B-025
Porsche Approved
Volkswagen 502.00/505.00,503.01


Typical Properties

Mobil 1 0W-40

SAE Grade 0W-40
Viscosity, ASTM D 445
cSt @ 40º C 80
cSt @ 100º C 14.3
Viscosity Index, ASTM D 2270 187
Sulfated Ash, wt%, ASTM D 874 1.2
HTHS Viscosity, mPa·s @ 150ºC ASTM D 4683 3.6
Pour Point, ºC, ASTM D 97 -54
Flash Point, ºC, ASTM D 92 236
Density @15º C kg/l, ASTM D 4052 0.855

Since I have had my turbo in, I have been using Amsoil 20-50, especially since this has been one of the hottest summers on record in the North East. I will go to 10-40 in the winter.

Just remember that "race oils" have less detergents in them but more additives to reduce friction. In other words they will ultimately break down faster but they lubricate better. Since they change the oil after every race, how long it lasts isn't terribly important as long as it lasts the entire race. They obviously do last that long.

can i get someones opinion on castrol gtx 5w20; is it basically the same as the brands mentioned above?; went to a large auto store, and that was the only 5w20 they had; gonna need to do my first top up of my new 8 and want to know what to go with for top performance;
as well, any canadians out there, where do you buy your oil; i went canadian tire and all they had in 5w20 was the castrol; any other stores i should be looking at? thanks

yeah, I'm sure your rotary engine prefers the taste of Castrol GTX over the taste of Mobil 5000, like anybody here can put their finger on it with data rather than subjective opinion, whatevah ... :rolleyes:

Staticlag, thanks for the linky. I just found a vender in my back yard, so to speak. If its good enough for rotoraygod, then I have to the very least give it a try.

I don't know how you can say that. Don't tell me you can't FEEL the difference between regular oils vs. synthetics, when running them in your engine? I'm justing saying this to illustrate the issuse. Not all oils are created equally.

Racing Beat recommends it too!

Going along with rotarygod...do not use racing oil in a street car!!!! They are meant to be changed right after an event...aka your talking about just a few hundred miles per interval.

Lack of detergents can cause serious problems in a street car...even with short 1-2k intervals.

Btw, mobil1 0w-40 doesn't get favorable reviews based on UOA's. Its point spread is so far that it tends to sheer out of grade all over the place, and alot of the chemical makeup is just to try and keep the viscosity in grade. Most people would recommend a 0w-30 as the maximum viscosity spread you want in your engine. The most sheer stable oils are the ones with the least spreads, like 10w-30, or 5w-20. (20 point and 15 point spread). This isn't to say that 0w-40 won't get good results in "your" engine...just that its not one of the favored oils.

Sheering is when an engine oil leaves its specified viscosity range, and jumps to another. The old mobil1 5w-30 synthetic (prior to the 5000, 7500, and 15000 marketing campaign) was well known for sheering to a 20wt oil after just a few thousand miles. The oils with less spreads also use more of their chemical makeup in actual chemicals which clean and protect, other then trying to prevent sheering.

On a counter point, many individuals find excellent results with 5w-40 weight oils. The only true way you can know whether an oil works in your particular vehicle or not, is with a UOA (Used Oil Analysis).

http://www.blackstone-labs.com

I'd also recommend the Dyson Kit, which has an actual tribologist (terry dyson) look over your particular UOA and give recommendations to tweak the particular oils your using for maximum protection/performance. Terry was actually the tribologist for some of the Mazdamotorsport teams...

Damn, you know a lot. You are now my Oil Sensei

I actually don't know that much...I just base my comments off of what the more knowlegable folks say over at BITOG.

If you are interesting in learning more about the complexity of engine fluids, give them a visit, its a good spot to stop at while your bored at work!

http://theoildrop.server101.com/ubb/ultimatebb.php

Thank you for the link, I will do some more research!

I want to use RP synthetic but have this 'fear' of using synthetic on a rotary. I guess I have to get over it.

My fear stems from numerous comments and PDFs, etc that say 'don't use synthetic oil on rotary engines' - some from Mazda, etc.

Maybe these were for pre-Renesis engines that didn't meter the same amount of oil into the engine housing... not sure.

I'll probably just switch to Castrol GTX 5w30 or 10w30 with the GF-4 rating and get out of the 5w20 race altogether.

Founds some GC (German Castrol) today M04 batch at my local Canadian tire, so I got a case. I only have 3000km on my car so I have to wait a bit. I'll probably switch at around 10000km to the stuff. It truly IS green, pretty neat that I found some of this stuff still lying around!

I will likely use the Lucas UCL and some 2 stroke ISO-EGD rated oil as a pre-mix, but I haven't had any luck finding the 2 stroke that was recommended. I'll keep searching!

Thanks again for the advice.

I use Royal Purple 5W20 in a pre Renesis rotary that was intended to use conventional 20W50. No problems and I am hard on that car.

My '91 Miata gets Mobile1. My 8 gets Penzoil 5w20. I don't understand the love for synthetic. The car burns oil by design and was designed to burn conventional oil.

Feel the difference, in a rotary???? Are you God or something? :confused:

My issue is not what is equal, but what is adequate. Most people will never even keep a car long enough to ever know the difference. You would be better advised to worry more about modding the MOP or using premix than what specific oil brand you use. Any major brand meting the manufacturer specification and change schedule is more than adequate. .

take two placebos and go to bed, then call me in the morning to tell me how great you "feel" :rolleyes:

just curious to know how many of the people here who are so fastidious about their oil are also the same ones running 87 octane gasoline ... now that would be rich

(raises hand)

I use Mobil1, and run 87 octane.

anyone use Trust F2 Re Spec for Rotary 15W-50SL(fully synthetic)? any comment?

I use Castrol GTX 5/20 and run 93 octane. Tried 87 once and it made a poof sound as it idled. I took that to be the knock in a rotary :confused:

do you mean Trust F2 Re Spec for Rotary 15W-50SL(fully synthetic)?

What? :confused:

The subject of which oils should be used in the 8 have been covered many times in
these forums.

Personally I would not use ANY synthetic oils in my engine, as far as I am concerned
rotaries no matter what model should have Mineral Base Engine oils only.

This is the main reason why..

In these forums you will find an attachment from Gomez with a factory parts bulletin
to their distributors/retail dealers concerning the use of synthetics, for all rotaries
I think prior to the 8, that is all 10A,12A(B),13B and 20B Rotary Engines.

Each of the 2 rotors have 2 sets of oil control seals an inner and outer located in the
centre of the rotor, these oil control seals have a separate "O" ring that is manually
installed during assembly. These O rings can not be seen after installation of the
assembled oil control seals, however, it is these O rings which can break down,
virtually dissolve over time if Synthetic oils are used in the engine sump.
There are a total of 4 inner and 4 outer oil control seal "O" rings.
They have a shiney plastic look and feel to them.

The Factory Parts Bulletin specifically says DO NOT USE SYNTHETIC BASE OILS.

Although the RX-8 oils seal "O" rings are a different part number, their principal of
design/look and assembly are exactly the same as other models.
I can't confirm if their compound is different to pre RENISIS engines.

Here in Australia Mazda does not recommend synthetic engine oils for
the RX-8.
There are many stories where the polymer base compounds in Synthetic oils
actually leave burnt residue balls behind in combustion chambers/rotors also.

Basically the so called benefits of synthetics and use in Rotaries are something
I would keep away from....

Hope this helps...