JIM5.0

In Texas, we are having recod heat. Our temps are 110+ degrees F everyday and will stay like this all the way to October, maybe even into October too.

I am ignorant of what weight oil I should use. I bought 8 qts of 10w30 RP full true synth. I have 5w20 in my car right now.

Is 10w30 better suited for the heat than 5w20?
If not, what should I be using?

DreamerGT

I been running 5w20 in my car for years, to no ill effect. 10w30 is fine your motor wont know the difference.

JIM5.0

Good to know. I know 5w20 does not do S*** to help save you gas so I have no shame in discarding it for 10w30.

Unleashedbeast

I actually gained efficiency by switching from Mobil 1 5W-20 to Amsoil SSO 0W-30. Here is what I know you will gain in hot weather by using a true synthetic 10W-30 like Royal Purple.

1. Better shear stability
2. Lower NOACK Volatility

This link pretty much covers your situation. Read post #30 and #31

Team Shelby: Why 10W-30?

uberstang1

Good post, I've always ran 10w30 on my setup but Its also stored in winter.

Unleashedbeast

a true synthetic 10W-30 is the perfect lubricant for a modular when used in hot weather.

JIM5.0

Thanks so much fir the info! I am glad I did dump the CAFE 5w20 lie fir the more traditional 10w30 oil.

Speaking of heat, central Texas just say it's hottest day ever in history: 115 degreesF in the shade!!!
And I was stupid enough to change my oil in this torture

Unleashedbeast

I know what you mean Jim, as I have worked on my car laying on concrete that was directly in the sunlight at midday during the hottest months of the year. It's called PASSION!

Soldier GT

Da** this is some good info to know...