I don't want to start an oil war but just want to know if 5w-20 Royal Purple synth oil is OK to use in these engines and whether it burns OK? Previous owner was using it so I just continued to use it. Engine uses about 1 qt. per 800 miles right now @ 82,000 miles.

 

if you mean “needlessly burn the cash out of your wallet”, it’s your choice ...

all I mean by that is synthetic is generally considered acceptable

and ime the people using RP typically have fallen for a candy purple marketing shtick that paying more for it somehow benefits their Renesis engine.

it’s certainly not any better benefit than any other synthetic, and could be argued to not be any better than a good quality dino oil either wrt the Renesis engine.

you would probably be better off bumping it up to at least a 5W30 or 10W30 grade regardless of brand/type
.

 

^^ +1
​​​​​​I ran it for a time years ago. It's fine but don't feel obliged to continue using it.

 

Synthetic is fine. BHR actually recommends it.
I run amsoil 5w50 in mine and it seems fine but I ya e low miles and track the car.
That being said I think team hit the nail on the head. If you want to use purple do it but I would at least go 5w30

 

I used the RP 5w-20 for little over 3 years. UOA's looked fine. If you want peace of mind about using it, RP's website specifically addresses use in rotary engines. At the end of the day though, if you're changing the oil at the recommended intervals, I can't say I'd recommend using RP because it is more expensive. There's plenty of RX-8's here with high mileage that used cheaper oils.

 

I am running RP 10W30, have been since I bought it 18 or so months ago. No argument that it's more expensive as mentioned. I buy it in the jugs which brings the price down a bit.

 

Thanks all for the advice. Still going to stick with Royal Purple but I'm changing from 5w-20 to 10w-30 since I live in NC and summer will be upon us soon.

 

I have been running RP 5w20 for the last 30xxx miles.
literally switching to 5w30 right now. Hoping my reasoning is sound but with the 117 degree weather I’m noticing something different. I’m hoping this helps.
btw I’m wondering if there’s a procedure for switching weight. I’ve heard it’s gotta be done like a flush. Is this accurate?

 

You don't need to do anything special when switching weight. 30 or even 40 is definitely better for high temperatures.

 

Loki I have two new member posts that truthfully have been waiting for exactly you.
hahah never mind your already on it
Ima try 30 just cuz it bought and opened lol. I have two newish oil coolers for install. O Ming shortly

 

Like Loki said no need to do anything but a regular oil change. The two oil weights mix with no issues. Having said that, tipping the car just a bit will get more oil drained than when it's flat. DON'T tip it on jack stands, only if you are just jacking a side.

 

I live in South Louisiana and will not run watered down 5 wt oil in my car.
Castrol 10w-40 in the pan and Idemitsu premix in the tank.