BillK

You just spent $30K on a new car and aren't willing to fill with premium to allow the engine to give you the highest performance it's capable of? This doesn't make sense to me...

rotary-tt

Can someone please post the exact text from the Owner's Manual regarding oil here? All of us on the www.rx7club.com have been having this dino vs. synthetic discussion for years.

In short, I would say that Mazda approves of synthetic oil if it is not explicitly stated to not use (as in the Owner's Manual of my '93 RX7).

FYI: Most synthetic oils burn with less ash content than dino and have better lubricating and breakdown properties and handle higher heat. Mobil now recommends Mobil 1 for my '93 rotary on their web site. And Royal Purple is quoted on the official Mazda web site at SevenStock as saying synthetic is fine for rotaries. Many of us on the RX7 Forum have been running synthetic for years. Don't believe anyone has had a motor fail due to lubrication (usually the coolant or apex seals go).

BillK

The page from the owner's manual I saw posted just says "energy saving" oils which, frankly, all owner's manuals say. It's generally a reference to the SAE ratings (e.g. SF, SG, SH, etc.).

The manual page did not specifically address the synth vs. dino question, but take this for what it's worth:

The manual specifies 5W-20 oil.

There's only one source for 5W-20 at the moment, and it's a dino oil available at your Mazda dealer...

rotary-tt

I use Royal Purple 10W-30 in my 13B-REW.

For your RX-8, the Royal Purple web site has 5W20 synthetic available http://www.royalpurple.com/rpmor/rpmor.shtml

The '93 RX-7 manual explicitly says not to use synthetic. If the RX-8 manual does not explicitly say this, I'm sure it is just fine to run synthetics...

Also, the Formula Mazda series motors are sealed with synthetic oil...

tpryor

Actually, the Technical CD SPECIFICALLY says the motor was designed for 5W-20 NON SYNTHETIC oil.

Castrol makes a 5w-20 dino oil. Wal-Mart, Sams, Napa, etc. ALL carry it (I've been shopping for it since seeing the Technical CD).

8_wannabe

Regardless of what I do I won't get the highest possible performance from this vehicle. That's not how I drive. I don't do power acceleration, rev at high rpms, race down the freeway, whatever. The marginal performance decrease I'll get from lower octane will be far masked by the lower performance style in which I drive. As long as I'm not doing damage to the engine, I'm a happy camper. BTW, we went through the same thing with my wife's BMW 323i. Everyone said you gotta use premium, the dealer and maintenance techs said you gotta use premium, the owners manual said premium recommended but 87 and above is ok. We've been using 87 for four years now and none the worse for it.

And guess what, I'm not going to change the oil at 3000 miles or 5000 miles or whatever. I'm going to follow the owners manual maintenance schedule for the type of driving I do and change the oil every 7500. Of course, I will check oil level and keep it topped off; I realize the Renesis consumes oil. I just don't fall for the corporate hype that tries to push you to get more/better/faster; I'll read the non-hype guidance and do what it says. And I'll sleep perfectly well at night.

rotary-tt

Well then there's a huge discrepancy (and oversight) between the Owner's Manual and the Technical CD. Looks like Mazda has chosen to let the syn vs. dino debate live on :D

Well if I get an 8 for the 'family' car it will run Royal Purple (after break-in with dino). Waiting to see what bugs come up in the new 8 first. The first year '93 RX-7's had a laundry list of TSB's compared to the '94's and '95's.

ChrisW

Interesting choice of numbers. UK Premium Unleaded is rated 95 RON, so that would mean we will have to use Super Unleaded (97/98 RON) to get the best performance.

rotary-tt

More fuel to the oil fire :D

http://www.mobil1.com/index.jsp

Listed below are the oil viscosities that your vehicle manufacturer recommends for different temperature ranges, as well as the Mobil 1 motor oil that is suitable for your vehicle. You Chose The Following Vehicle:

Make: Mazda (edit)
Model: RX7 (edit)
Year: 1993 (edit)
Engine: 2RTR-1308cc 80 (edit)

10W-30 Above -13° F
You can use Mobil 1® with SuperSyn™ 10W-30 with confidence. This viscosity is also available in Mobil Drive Clean Oil™ and Mobil Drive Clean Plus™ High Mileage formula.

5W-30 Below 32° F
You can use Mobil 1® with SuperSyn™ 5W-30 with confidence. This viscosity is also available in Mobil Drive Clean Oil™ and Mobil Drive Clean Plus™ – both the Newer Vehicle and High Mileage formulas.

RX8 Seller

Just wondering? why the issue with the oil? I am not an owner of one, but I would tend to believe the people that make the motor, not the oil? Why would anyone that spends this much money for a car that is this special and even risk it?

Richard

Quick_lude

Richard, most of the piston cars out there save for some high priced machinery like Corvettes,Porsches still recommend regular oil. While that is adequate, regular "dino juice" still cannot beat fully synthetic oils (PAO or ESTER based) in many if not all performance criteria. So your logic is flawed, if the engine manufacturers really wanted the best for the engine, they would recommend synthetic oils.

The rotary is a little special as we've seen when it comes to motor oil. I've read many threads and I'm still not sure if I would use synthetic or dino. And like I've stated before, if the European and Japanese engines recommend higher viscosities like 10w30, 5w40 I will use those and not the 5w20 that's recommended in North America for most of the new engines, piston or rotary, only for CAFE requirements.

rotary-tt

Read this concerning the differences between dino and Royal Purple and let me know if you still like dino: http://www.royalpurple.com/rettech/retwhyrp.shtml

Not sure why the tech CD says no synthetic when the Owner's Manual says it's ok (if it weren't it would explicitly say so like my '93). It would say something like 'synthetic oil would void your warrenty...' If it does not say it then it's ok.

Like I said no one has ever had a rotary die from lubrication problems(or very few, never heard of one on the www.rx7club.com forum). Rotaries blow apex seals from detonation and coolant seals from overheating, etc. I put 135K miles on my '86 driving 7k rpm daily before it died (due to blowing a coolant hose and overheating). Put well over 100k miles on the '79 before selling it and it still ran fine. Now the '93 is on it's second motor (before I bought it with 74K miles) which is very common for the twin turbo REW motor longevity (without proper care). I can tell you that my '93 runs better on Mobil1 or Royal purple than any dino I've put in it. It's common to get a 10 deg coolant temp drop with synthetic...