5w or 10w/30? Options

[mwpayne]

Just bought a '95 celica ST. Needs an oil change, is 5w/30 ok? Reason is I also have a 2002 camry that uses that, it would be nice to stock one oil for both cars..

[Supersprynt]

Your right - kinda. The W isnt just for "winter" its just plainly the viscosity of the oil when its cold. The most wear in an engine come from start up, this is generally when theres no oil pressure and oil hasnt reached every where yet. so a thick oil will take longer to get everywhere while a thinner oil will reach vital parts quicker. Thats the first number in say 10w-30. 10 is the viscosity of the oil when its cold, 30 is when the cars warm. So 5w-30 is the same as 10w-30 when your engine is warmed up.

So theres pros and cons to using a thicker weight oil. 5w will get to your engine parts quicker while the 10w will take longer. And the 10w will add some cushion but take longer to get to the parts. And in the end when yoru cars warm they're both the same.

You'll be fine with a 10w-30. Semi or full synthetic is what i'd recommend for the age of your car.