Come on man do your homework figure out what the characters mean on a oil container...
what does the 5w stand fore? what does the 40 stand for...??????
5w-40 is a multi grade oil.
The w in "5w" stands for winter and the number itself stands for cold temperature viscosity. The 40 stands for hot temperature viscosity.
Now lets compare a 5w-40 to a 15w-40. Both are multi grade oils. Which one would be best on a cold chilly day to start up an engine or use in generally cold weather?
5w-40 would be best on a cold day because the viscosity is lower, the oil itself flows better and is less thick than 15w-40 oil.
5w-40: So when the temperature(of the oil) is cold the oil acts as 5 weight, and when the temperature (of the oil) is hot the oil acts as a 40 weight.
Best if this is used in a generally colder climate.
15w-40: So when the temperature(of the oil) is cold the oil acts as 15 weight, and when the temperature (of the oil) is hot the oil acts as a 40 weight.
Best if this is used in a generally hotter climate.
You do not want to use thick oil in cold climate temperature because of poor lubrication issues and the cold temps will make the oil act as a lower viscosity.
You do not want to use thin oil in hot climate temperature because high heat can break down the oil and make it act as a lower viscosity oil when you would infact need a higher viscosity.
Most engine wear occurs at start up but thats a whole other issue...kind of. so just make sure you have the appropriate oil weight for your specific climate.