It shouldn't affect it at all. A big reason the manufacturers went to 20-weight oil is fuel economy. The US government has a standard called CAFE - Corporate Average Fuel Economy. Wikipedia has a good article on it. To meet this standard they use every trick in the book, and one of them is thin oil which is easier for the engine to pump. Once you get the car home, you can put 30-weight oil in it and not hurt anything.
NO, stick with 5w20 or 5w30 if the mileage is over 100,000.
typically 5w30
5w30
5W30.
5w30 any major brand.
in a 2002 honda accord
5W30 any major brand.
5W30 in winter and 10W30 in summer.
No, I suggest you use 5W30.
SAE 5w30 any major brand.
SAE 5w30 any major brand.
According to alldata the recommend grade of oil is 5w30.