I've been using this for a year now and was wondering what the difference is between the 5W and 3W on my 1997 Accourd Wagon...this stuff has really stopped my leaks and the engine runs a lot smoother.

 

wow, i didnt even know they made 3w30 oil. but now that i know, the two numbers represent viscosities, or resistance to flow. the higher the number, the more viscous it is (ie. water has a low visc, honey has a high visc).

first offthe first number refers to viscosity when the oil is cold. the second number refers to the viscosity at operating temperatures. (well, not really, but its like this: a 5w30 oil, when hot, will have the viscosity of a SAE30 oil when hot) this probably doesnt make any sense because its 6:30am for me.. so let me sum it up: 5w30 oil is slightly thicker than 3w30 when cold. when theyre warm, in theory, they should be the same. thicker oil protects better, but also decreases fuel economy, and makes it slightly more difficult to start your engine if its REALLY cold. hope that helps

 

how many miles do you have? also where do you live?

 

Got 177K...here in Charleston SC. Broek a main seal 2 years ago and have been using this stuff ever since. Seems to have slowed the leaking...

Thansk Guys!

 

No real reason for that low cold viscosity in SC. I would say 5W30 but you could do 10W30 also.