Percolation? Heat soak? Don't drive during summer??

yellow rose said
EXACTLY. I’m at 170 now with a 5W30 and I’m going to drop down to a 0W20 and a 160 thermostat.

You can’t just start dropping coolant temps without looking at all the systems and accounting for them.

So would it be beneficial to run a lower viscosity oil? I thought I read the thicker viscosity oil was beter in warmer climates, plus the 20w50 is the only viscosity in the Vr1 at the auto store.