bNguyen

Hey all, I took my 2nd Gen RX7 in for service because I wanted to make sure what needed to be changed and so forth. While in service they changed my oil...the factory shop says 20W50 but the oil that was placed was 5W20. I was informed the 5W20 was used in the RX8 but can you please tell me if anyone out there who has an old RX7 can tell me if this "new" oil for the RX8 is usable in a 2nd Gen RX7. Thank you

KKMmaniac

I wouldn't unless driving in ~0 deg. F temperatures. The Renesis was designed (or so we assume) to use 5W-20 oil, and the oil is well cooled by the twin (our 6-sp. anyway) oil coolers.

I use 20W-50 in my 1st gen. RX7 which I drive during the summer only, but then it has only the beehive (coolant cooled) oil cooler, which isn't nearly as effective for cooling as your air-to-oil cooler. I don't think the 5W-20 would have the film strength required for good protection at warm temperatures in the 7.

Zootx8

I used 20W-50 in both my '86 and '87 7's - I'd also stick with that, I'd be a bit miffed at the guy who did the oil change.

mzdoggmann

In this case, is the 5W20 oil still standard for the RX-8 even in warm climates like Florida or southern Cal in the baking summers?? Or should swap to a thicker oil during the hot seasons. Anyone w/ expertise pls advise.

Zootx8

there should be a temp range for the oils in the manual, it's in the car right now otherwise i'd look it up. i believe the 5W20 recommended covers a pretty broad temp range, but if you thought you'd be out of that range switching to a 10w30 may not be a bad idea.

Nubo

It's notable that Mazda specifies 5w30 in countries outside of North America. There wouldn't appear to be a mechanical reason for avoiding it.