It's a little heavier then I would use, but if that's what you have, that's what you run. It's likely very good oil and has the additives your older engine needs, what is weather like where the truck is? If its really cold, your oil pump will be working pretty hard. Hotter temps, no problem.
I use 10W 30 so that's what I suggest. A 20W 50 seems a bit viscous and I would have guessed it was for a big diesel truck but I see it's for "essence" too.
34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
That would be 43-86 degrees F, not a brutal range. My 1948 owner's manual advises straight weights 20W or 20 for that temperature range but they probably didn't have 10W 30 or 20W 50 then. 50 at the hot end is half-way to gear lube for the rear end. Too thick for me.
You should post some pictures with what has to be great scenery.
34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
Another oil debate. I use 15w40 in my 38 and 53. I'm not sure 20w50 would necessarily be too thick in the summer. We need to remember that oil thins as it warms up so the 50 hot may be thinner than the 20 cold. I don't think I'd use it in the winter. Having said that I drive both of my vehicles year around and 40 isn't that much thinner than 50.
Save a life, adopt a senior shelter pet. The three main causes of blindness: Cataracts, Politics, Religion. Name your dog Naked so you can walk Naked in the park.
For some reason I really enjoy the discussions about oil. Today I just bought a jug of 15-40 as I'm changing oil tomorrow morning. My first experience driving the truck a few years ago, I put in 10-30 but found the oil pressure was too low.