I have a 2010 Sonata and the manual says to use 5W-20. Any of you gearheads out there know what the disadvantage to using 5W-40 instead of 5W-20 are? Thanks in advance.
Nevermind. Searched the message boards and most don't find much of a difference between 5w-20 and 5w-30 but they find that there is about a 7% decrease in fuel economy when you go all the way to 5w-40.
Last edited by yada,yada,yada; 05-03-2013 at 05:06 AM..