Royal Purple engine oil: 10W30 or 20W50?
 

Both of these viscosities seem popular among board members.

Which would be better for my climate? (Oklahoma)

10W30 or 20W50

Thanks,
Victor

20w50.

I run 15w50 mobile1 in my car year round. Or maybe it is 20w50. I am not sure, even though I just changed it yesterday. :)

i would say in O-town use 10-30 in the winter. isn't it like 5 deg there? lol

You should not be running 20w50 in winter, period. The oil is not designed to flow well in cold temps. Stick with 10w30 and run 20w50 in the summer, if you want.

I run 20w50 Amsoil all year round in my TII and will in my FD once that is up as well. But of course, I live in Arizona, so cold temps are usually not too cold at all:)

I have been running the 15w50 for years with no problems.

Run 5w or 10w-30 in the winter, and 20w-50 in the summer. If you want to see why, take a bottle of 20w-50 and put it outside in 10 degree weather. I promiss you will think twice about running it in the winter. :)

I think 19 degrees is the coldest I have seen here this winter. And these little rotaries are hot running little bastards. :)

The danger isn't when the car is running, its at inital start up. I am telling, put a quart outside and then you will see how thick the oil gets. Now imagine when you first start your car, it takes awhile for the oil to start flowing threw the oil passages. Most damage is done durring initial start-up.

It just doesn't make sense to run 20w-50 in the winter.

I have an oil temp gauge, and I can tell you, there is ABSOLUTELY NO reason to run 20w50 in winter. However, there are very good reasons not to.

Unless you driving your car on the track or in very hot climate, there is no reason to use anything other than 10w30 (higher range synthetics not included).

I read you guys sayin you are runnin mobil 1 and amsoil, and thous are both synthetic, i thought you wernt sposed to run synthetic unless you have like a race built rotary motor?

Let's not start the synthetic vs dino juice debate again here. Suffice it to say that quality synthetics are fine to use and MANY FD owners use them. The one thing that's not debatable is that synthetics are better for your turbos and they certainly have a much higher heat tolerance than dino juice, which is good for the track.

In the northwest I run 10-30W in the winter and 20-50 in the summer... FYI

I swear by RP oil.... I run 20W50, even now in the winter time I use 20W50 RP. I DID use Mobil 1 15W50 like 2 oil changes ago ( 2 months), saw a notice, but still went back to 20W50.

-Dan

thanks for the replies

i will do 10w30 for winter and 20w50 for summer.

Been using 20w50 and car runs superb...

10w-30 in winter or you will risk lubrication starvation at startup. RP baby !

about the synthetic thing, I am running premix and no oil injection, which is one of the arguments to not run full synthetic.