Hi all, i just got my first oil change for the dealership today. they put in w5-30 in the car instead of w5-20 which was on the oil cap and told me that both w5-30 and w5-20 are about the same. is that a correct statement?

thanks

 

The short answer is yes. They will work similarly. 5w-30 will act as a 30w (viscosity) inhot weather and a 5w in cold. Transversely,5w-20 will act only as a 20w in hot weather. That's why I choose 5w-30. Texas summers are... well... rather HOT!! [sm=icon_rofl.gif]

 

If you live somewhere where it is very cold in winter, 5w20 is a better choice, it's a bit thinner, meaning it will flow betterwhen you start the car up when the ambient temp isvery cold.

If you live somewhere temperate, I think 5w30 is preferable, it has better shear strength (meaning better protection once your engine is warmed up).

 

What he said... ^^^
The "w" in the ratingstands for"winter" not weight and therefore will act (flow) like a 5 weight oil in colder weather. Easier starts and quicker flow for better protection sooner.

 

Thanks for the advice, i live in Colorado which can get very cold. i hope it will not be too bad to used 5w-30 in the cold