Is 20W-50 too heavy for my 340?

I use 10W30 since 2004.
My only gauges are what came on the factory rally dash.
I don't have an aftermarket oil pressure gauge, so I have nothing to worry about. Just Like I don't have an aftermarket temp. gauge, so again no worries. Without worries, I can just driiiive it, lol.
well, to be truthful, the 367 is wearing a deep pan and a high-volume oil-pump.