Is it smart to switch to a thicker oil in the sense id go from 5w30 to 5w40. My car calls for either 5w20,30,40 but ive seen that many would rather choose 5w40 because my vehicle is a tubrocharged car and it holds up to the higher temps outputed by the turbo. My car is a genesis coupe and it has 125k miles on it and I dont know what previous oil viscosity was used, So im not sure if changing the thickness would would cause any problems.
I also see that 5w40 oils are usually API SN rated and 5w30 is API SP/ILSAC Gf6. Not sure if this makes a difference.
I also see that 5w40 oils are usually API SN rated and 5w30 is API SP/ILSAC Gf6. Not sure if this makes a difference.