Gord96BRG

There is NO risk. Mazda specifies the oil to be used must meet API SL, 5W20 grade. Period. That's it. Nothing about synthetic or non-synthetic in there. RotoRocket is wrong in his statement.

If you run a synthetic API SL 5W20 oil, you're meeting every specification Mazda made. 100% warranty compliant.

It is available in the US at AutoZone and other stores - Castrol Syntec 0W30, often referred to as GC (short for German Castrol). The bottle says Made in Germany, and it's a full group IV PAO synth. Even better, it's got a very special base stock by all analysis, and is often considered to be the best synthetic oil on the market right now. Castrol Syntec 5W40 used to be produced in Belgium, and was also a PAO synthetic - and was the front runner for use in VW/Audi engines with their special requirements (505.1 spec, IIRC). It was referred to as BC, but the latest batches of Syntec 5W40 are produced in USA, and it's suggested that they've switched it to a hydrocracked group III base stock. It still meets VW 505.1, though, so is still a great oil.

Regards,
Gordon

cjkim

semi thread hijack BUT...
I've read many threads about how synthetics can cause damage and many where that claim seems to have pretty much been disproved now, BUT, I've never really seen an explanation as to why you would change to synthetic. Would the benefits received from a conventional piston still apply? Basically asking, what are the upsides to moving to synthetic vs non-synthetic?

RotoRocket

iTrader: (1)

Gordon - I believe somebody emailed Mazda North America directly (someone from here), and asked them if synthetic oil was acceptable for use in the rotary, and the direct answer was negative.

I'm working on finding the thread now.

RotaryGod- You've provided a lot of great info, but maybe your apt to be a tad dismissive on the synthetic oil conundrum (again, not whether it's good or bad, but whether Mazda has an issue with it).