IamFodi

iTrader: (1)

Few caveats:

1. Between the Mazda TSBs, this archived post from MazdaspeedKB.com, and a bunch of stuff already mentioned here and elsewhere, it definitely seems that people who drive mildly might want to avoid synthetics. People who drive the car as it's meant to be driven should be fine with whatever.

2. Certain papers and oil formulators' statements strongly suggest that ashy additives are important to avoid as well. So, no "performance" oils with hysterical amounts of Ca/Mg/Zn/P/Mo/etc.

Sticking with an ILSAC-rated conventional xW-20 or xW-30 may not be necessary, but it is a convenient way to tick all the boxes without much thought.

Beyond that, yes -- any reasonably additized oil should be fine as long as it matches your driving, and your OCI needs to be sane.

Strigidae

Thanks for the help! I think I'll be using some WallyWorld synthetics

TeamRX8

iTrader: (25)

There’s nothing wrong with Mobil1, Castrol Edge, etc.

UnknownJinX

It's actually quite simple.

Go to your local auto store, see what's on sale, check to see if it's a reputable brand(Pennzoil, Castrol, Mobil 1, Quaker State, etc.), and grab 2 or 3 jugs, done.

Adjust the viscosity as needed. Where I live, 5W20 is fine, but if you live in Texas or California, you might want to consider 0/5W30 or 0/5W40 if you drive hard.

I personally buy either Castrol GTX conventional(not available in 5W20 or 5W30 anymore; it's now a new semi-synth blend) or Pennzoil conventional for CAN$20ish a jug when they are on sale. Synthetics don't go on sales as often, and even when they do, they are still pricier.

IMO synthetic's much better if you don't want to do oil changes as often, but as we can all agree on, it's a good idea to change oil often on this car, so that kills off the main benefit of synthetic.

There is also the more even molecular size of the synthetic oil, but I am not sure how much that will come into play.

Royal Purple is mostly marketing hype. Not that I really care because I never see them locally anyway.

For reference, I use mine as a DD, but I rev the crap out of the car whenever condition allows. If it's rainy out, I usually stay under 5k RPM, but if the ground's dry, I can beeeeeeeep at least once each trip.

I think there is an S1 new owner video made by Mazda that the long-term effects of synthetic oil is unknown and they don't recommend it.

Edit: This is the one I am talking about. Jump to around 4:50 mark.

IamFodi

iTrader: (1)

There are three main benefits:

1. Longer OCIs
2. Better performance at very high temps
3. Better pumpability at low temps

You addressed #1 and I agree. A synthetic will generally withstand contamination better than a conventional, but we shouldn't be re-injecting those contaminants into the combustion chamber anyway. The other reasons to change oil -- additive depletion, base oil degradation, etc. -- are equally well served by a shorter OCI.

#2 is only an issue if there are any lubricated parts in the engine that get that hot. A turbocharger is one example. Certain piston engines apparently also have really hot ring packs. In these kinds of situations, you might benefit from a synthetic no matter how short your OCIs are. It's unclear whether anything in a stock NA Renesis is in this category, but I suspect not.

#3 sort of helps indirectly. If you look at a 5W-xx conventional and a 5W-xx synthetic, both will be comparably pumpable at low temps. But the synthetic will generally have made fewer compromises (volatility, shear stability, etc.) to get there.


Thats just a way to describe the purity and uniformity of a synthetic basestock. It's meaningful chemically, and it sounds cool, but it's not worth dwelling on as a layperson AFAIK.


Really? You're missing out.

gwilliams6

Thanks UnKnownJinx, that is the video that came with my 2008 RX8 and was supplied for S1's, at least in the US.

UnknownJinX

Some good explanations and knowledge here.

I will bring it to AutoX events once I get it off winter tires. Whenever the ground's dry(like last night), I take some twisty roads around me and rev its heart out.

NotAPreppie

It's important to note that parts stores that sell their own brand of oil don't actually make it themselves and often don't even have their own internal specs for it.

For instance, O'Reilly at one point was selling Valvoline Synpower in their own bottles for ~$18 for 5 quarts an a filter. This was back in 2010 but I doubt the practice has changed much.

https://bobistheoilguy.com/forums/ub...base-oil-quali

StealthTL

iTrader: (1)

Just for info, Shell makes some pretty good oils in it's Rotella range, and also makes all Quaker State and Pennzoil lubes.

When they bought Pennzoil, they also got 'Slick50' and the entire JiffyLube chain, but I'm sure we can cut them some slack.

The Pennzoil Ultra Platinum synth has some excellent 'test results'....if you know what I mean, nudge nudge, wink wink.
(ILSAC GF–5, Sequence IIIG piston deposit test using Ferrari specifications.)

IamFodi

iTrader: (1)

The main thing I like about SOPUS brands (Shell, Pennzoil, etc.) is that most of their "synthetic" stuff is largely or entirely GTL. It's slowly trickling out to other manufacturers, but few other products use it yet.

Of course, that's just the base stock, which isn't nearly so informative as the spec. But AFAIK, a GTL-based oil is a little more likely to run cleaner than a regular Group III-based oil, all else equal.

NotAPreppie

I don't know about the latest version of Shell's Rotella but in the past it had significantly more ZDDP (Zinc dithiophosphate) than gasoline motor oils. It's a really good anti-wear additive.

However, this can be an especially large problem for rotaries that still inject crank case oil because ZDDP contains three significant catalyst poisons (zinc, sulfur and phosphorous). Avoid using anything with significant quantities of ZDDP if you are still injecting crank case oil.

IamFodi

iTrader: (1)

Agree re. anti-wear and cat poisoning.

I wouldn't have used the phrase "significant quantities" there, because the amount of ZDDP even in a GF-5 xW-20 is plenty significant. But I assume you meant "large quantities", e.g. well over the 800 ppm phosphorus limit for API SN/ILSAC GF-5. If so, I completely agree.

Doubly so because more modern forms of ZDDP do a better job of staying in the oil. That means a given amount in a more modern oil is worth more than the same amount in an older oil.

More recent versions of Rotella may not have the high ZDDP counts that older versions had, but they meet tougher specs, so actual performance should be equal-or-better. Same goes for just about any oil, really.

wannawankel

How about the Shell Rotella Diesel 15w40 non-synthetic - does it have too high ZDDP levels? I use this in all my motorcycles (that call for 10w40).

IamFodi

iTrader: (1)

This? Shell ROTELLA® T4 Triple Protection | Shell ROTELLA®

If so: Shell Rotella T4 Triple Protection SAE 15W-40 API CK-4

Looks like significantly more than the 800 PPM limit, for what that's worth. Whether that's "too high" is impossible to say. I personally would want less, but that's a gut feeling. It's not obscenely high though.

TeamRX8

iTrader: (25)

I’d be less concerned about engine seals since zinc has considerably more lubricating properties than carbon and more concerned about fouling a cat converter

NotAPreppie

Who is talking about engine seals? And you've just agreed with IamFodi and I re: ZDDP's impact on catalysts.

Are you feeling okay?

TeamRX8

iTrader: (25)

It was stated previously by the usual suspect and apparently edited out. I also wasn’t referring to you Stealth. You obviously are more informed about it than people who read some stuff on BITOG website and go parroting it about.

lOOkatme

you want to run the thinnest oil possible at start up and want to run a thick enough oil to maintain pressure at the most extreme temps and rpms.

I have a sohn, and run 0w-30 synthetic. The high temp thickness between 20-30-40 isn't that much, where it really counts are cold start ups where the thickness of the oils are vastly different between a 0 and a 5 or worse a 20.

StealthTL

iTrader: (1)

If you like thin oils, 2018 will be a 'good' year.....

You will meet the new CK-4 oils, with enhanced shear stability and higher resistance to oxidation and aeration.

And the new FA-4 oils, formulated for newly redesigned engines, calling for a much thinner oil.

Already on-road testing at Cummins and Cat, and all the major truck companys.