Which brand of oil do you guys recommend? should I just go for Mazda oil?

In previous threads, lots of people use Castrol. So far, with two oil changes, I've used Pennzoil 5W20. Stick with a major national brand, and be sure to get the proper weight and API Service rating of SL.

I am also using the pennzoil.

I tried to get some Mazda oil from the dealer parts dept today, said they had it but couldnt sell it to me, that it's only for shop use or some shit.

Anyway I use Castrol GTX

I've used Castrol GTX as well...but am eyeballing some Royal Purple.

if you dont go with Mazda oil, go with Mobil 1. i havent heard any complaints yet and i know several turbo'd supras and IS300s that use it. just my $.02

Yep....Mobil 1.........that's what I use.

so 2 for Pennzoil, 2 for Castrol, and 2 for Mobil 1...i'll just choose one of those three then...thanx for your help everyone

I recently switched to Royal Purple 5W20, and it seems to work good. It could very well be my imagination, or coincidence...but it seems like I'm getting slightly better mileage.

I just measured my gas mileage today at 19.15 MPG for mixed city/highway driving on 87 octane, which sort of surprised me. I don't have the "L" flash either. I don't drive my car hard but I don't baby it either, typically shifting at 4-5k.

CASTROL!

I've got Royal Purple in the garage as well. Otherwise I'd be using Mobil 1.

How have you guys liked the Royal Purple??? Burn less of it?

Originally posted by MyRx-8yourcar
How have you guys liked the Royal Purple??? Burn less of it?

The "burn rate" is not going to depend on the oil, because the oil consumption is BY DESIGN. There are metering jets that inject the oil into the combustion chambers to lubricate the apex seals, etc. If a particular oil gives you a less than nominal burn rate, then I'd say you probably aren't getting the benefit of proper seal lubrication (read - short life).

Just out of interest for you the UK RX8 Owners Club have discount on oil for members at the moment 90% use Silkolene/Fuchs Titan 5-30W Semi-synth the rest Castrol A1 5-30W Semi

Motorcraft semi-syn 5-20. I guess I'm just one of those guys that uses the viscosity recommended by the manufacturer. I know it's probably a CAFE thing, but I've always thought a lot of work goes into the recommendation that we don't necessarily see.

PENNZOIL!

Originally posted by DAC17
Motorcraft semi-syn 5-20. I guess I'm just one of those guys that uses the viscosity recommended by the manufacturer. I know it's probably a CAFE thing, but I've always thought a lot of work goes into the recommendation that we don't necessarily see.

Yes, but it's worth noting that in the rest of the world outside North America, Mazda recommends 5W30.

Regards,
Gordon

Gordon: Point well-taken.

Thanks.

Penzoil here:)

I copied this info posted by gomez in the Australian forum from this thread http://www.rx8club.com/showthread.php?s=&threadid=21105

Quote pasted by Gomez:
Finally got an answer to this age old question, and an official answer at that.
I have a copy of a parts bulletin, distributed to all dealers, for circulation to Dealer Principal, Parts Manager, and Service Manager which reads as follows: (Sorry, can't copy it onto the forum yet...technical issues!!!)

Date 17-9-03!!!!!!
Quote:
Due to some misunderstandings in the field in relation to the use of Synthetic and Mineral oils in rotary engines, National Technical Dept have created this Tech Tip in order to assist your staff with enquiries.

Pre- Renesis:
All Pre-Renesis engines have a set of oil control seals in the sides of the rotors, which are designed to keep oil from the lubrication system out of the combustion chambers. Each seal consists of a metal scraper with a rubber o-ring within.

MC advise this o-ring is not compatable with synthetic oils (or synthetic/mineral blends) and that such oils can attack the material in o-rings, causing them to break down and deteriorate. Should this occur, excessive amounts of oil would be drawn into the combustion chambers causing high oil consumtion, smoke from the exhaust, fouled spark plugs and reduced engine life.Therefore, synthetic oils or blends are prohibited and only mineral oils must be used in early rotary engines.

Renesis engine:
This engine has similar seals, which perform the same function as with the Pre-Renesis engines, however, the o-rings are constructed with a completely new type of material that has improved longevity and compatibility with synthetic oils.

While such oils are not prohibited from being used in this engine, MC still advises that mineral oils are more suitable with these engines. This is why MA will be importing mineral based 5W30 engine oil.

Genuine MC Engine oil for Rotary Engines:
We are currently in the process of sourcing genuine MC oil from Japan. This is a straight mineral oil with a viscosity of 5W30. There is quite an involved process to import this oil and then decanter it, which is the reason for the delay in supply to dealers. When available, this oil will be dedicated for rotary use, whether Renesis or early models and only available to the parts departments of our dealer network in 5 litre and 1 litre packs.

We will advise part numbers as soon as stock is available for sales.

Aldo Schepis
Part Business Manager.
End Quote.

why 5w-20 here, but 5w-30 everywhere else? what's the difference between 5w-20 and 5w-30?

I use Valvoline 5w20 myself... not sure if I'm going to switch to Mobil1 yet. Since I plan on oil change intervals of 2500 miles, I doubt the mineral vs. sythetic debate would matter much, except to my wallet.

Hi Guys, note also that oil use is dependant on the rev's you average....ie, more rev's, more oil injected, therefore some guys with shares in Dunlop will have a greater oil consumption than the rest of us!!!

Gomez.

Originally posted by colin204
I copied this info posted by gomez in the Australian forum from this thread http://www.rx8club.com/showthread.php?s=&threadid=21105


Also on that thread was this pic (I added emphasis), which as far as I am concerned ends all doubt about use of synthetic oil in the Renesis engine, as well as the "requirement" for 5w20 weight oil.

maybe mazda says 5w-20 in North Americe because our gasoline and catalytic converters are different?

what part of the cycle is the oil sprayed into the rotor chamber? (what's the chamber called, anyway? in a piston engine, it would be the cylinder) I'm guessing maybe the oil mixes with the gas?

Castrol here.5W20. Keep it within 1/2 of full to full most of the time.

The oil is injected really slowly (drooled?) into the top of the rotor housing, in two spots, one for each side of the rotor.

It doesn't mix with the gas, just slimes the tip of the 'apex seals'.
.
.
.
doc

Using castrol oil since I got the 10 year 300,000 mile warranty from my dealer if I use castrol oil and cange every 4000 miles.
ers

Originally posted by zojas
what part of the cycle is the oil sprayed into the rotor chamber? (what's the chamber called, anyway? in a piston engine, it would be the cylinder) I'm guessing maybe the oil mixes with the gas?

Remember, we're talking about a very slow flow. If you're only using a quart ever 2000 miles, it would be like an IV bag in slow motion. Just enough to keep an oil film established between the seals and housing.

mazda oil is avalible at a very steep price $107 for 4 litres

http://www.corksport.com/main.php3?primNavIndex=0&mainURL=%2Fstore%2Findex.php3%3Fcat%3D214910

just for you guys wondering.and don't try to find it at your local dealer
I had mine changed at 700 miles just to get the muddy water oil slime out and have it documented for future warrenty work if it comes to it .and they put in 5-30w mobil in it.again a dealer doing a bad job.not even using the right oil in thier own cars...pitiful isn't it.........oh well I am serously thinking of going to synthetic anyway.I have worked at refineries and car oil is one of the lowest grades oil they make.......truth

Thank God none of you guys said you use Valvoline. Why would anyone use an oil in a rotary that is named after valves!!!

For standard oils I recommend either Havoline or Castrol. That's it. These 2 oils are actually very close to each others formulations. They lack alot of redundant additives that the other oils have that can lead to deposits. More additives aren't necessarily a good thing. I actually like Amsoil and Royal Purple the best.

I have used pure synthetics in older rotaries for years with no issues. Mazda used synthetic in the 787B LeMans car. I have never had an issue with them. Here is alot of useful info I posted in the past about synthetic oils as well as oil weight ratings.

http://www.rx8club.com/showthread.php?s=&threadid=22524&highlight=synthetic+oils

http://www.rx8club.com/showthread.php?s=&threadid=22698&highlight=synthetic+oils

For your info, the Mazda Rotary oil sold in Australia is packaged in Castrol containers.....

Mazda have made it plain, you can use synthetic in a Renesis, however, Quote: Mineral oils are more suitable. End Quote.

Read that to mean you will get better longevity with a mineral oil.
The Mazda oil retails at AUD$55 for five litres....

Gomez.

Gomez, thanks for the info on synthetics and mineral oils. I may have to mail order Royal Purple for my next oil change. I haven't seen that brand at the stores around here, only as a TV commercial on "Car and Driver".

Omg!!!!!!!! I did used Valvoline.... at the first bottle.... but I am using Castrol now... God... why would it happened to me..... so sad......!!!!!!!! tearingr me to parts.

Thank God none of you guys said you use Valvoline. Why would anyone use an oil in a rotary that is named after valves!!!


Other than the name, is there a reason not to use Valvoline?

I usually buy whatever is available at Walmart or Canadian tire.
API SL ILSAC GF 3 5w20, any brand.

Mobil 1 0w20

It's a little pricey at $6.46 a quart but I swear by it.

I used Valvoline because it was the only 5W20 I could find at my local Auto Barn, and I was low on oil. I didn't want to drive all over the place low on oil to find whatever boutique oil is in style. It said specifically it meets Ford and Mazda specs on the back of the container. It says nowhere on the bottle that it's synthetic.

I'd worry about anyone telling you not to use an oil because they find a non-rotary word somewhere in the brand name. That's just silly. "My car blew up at 50,000 miles and I used Valvoline" - that's what you should look for.

Gomez, thanks for the info on synthetics and mineral oils......

Anytime...

Other than the name, is there a reason not to use Valvoline?
I was being sarcastic. I'm just waiting for Rotaroline to come out.

What does this all mean "API SL ILSAC GF 3 5w20,"? Should I just be looking for the bottle to say 5W-20. Or does it have to have ratings for all that other crap? Ill probably get Castrol or Pennzoil. I just need a bottle of something to keep in the car ...

Anyone? Bueller?

Most of that is certification, and both Penzoil and Castrol should have the required certification, so just look for 5w-20 from either of them.