Is thicker oil, like 10w30 or higher, good for old piston rings and seals? If cylinder compression was low would switching to a thicker oil help?
So I’ve heard, just because it is due to engine wear and tear. the thicker oil will possibly help you not to burn oil if you are, I’m not sure about the compression, but it makes sense that it would.
Thicker oil = less performance.
I have always been a fan of Mobil1 synth and used it, but I have come to realize that with as many miles as my tired motor has on it that I am just throwing money down the drain by using it. So I switched to Valvoline synth blend. Not only does it cost half as much, I dont have to replace as much in between oil changes cause it doesnt burn as much… but back to your point…
I dont think that going from a 10w30 to a 10w40 is gonna make much of a difference, but I certinally wouldnt recommend going as far as a 20w50 or higher…