I was wondering what the differences are in the oil weight. Like 10w40, 10w30, 5w30 you get the picture. What do these numbers represent? And since I live in minnesota I hear running a lower weight is better durring the winter season?

BTW what oils does everyone use? I would use synthetic buy they are too pricey for me, so i'm using Valvoline Maxlife.

www.google.com

google is your best friend...

I just typed in "difference in oil weights"

and this popped up

http://auto.howstuffworks.com/question164.htm

but which one is best for our cars while being safe and not going too thin? or does the thickness not effect performance?

Well the different weights work better for different temperatures... Heat makes oil less viscous... so in hot wheather u use heqavier weight oils so they heat up more and become thin enough to run through the whole engine and lubricate better. In colder climates you use oil with less weight because they dont heat up as much as in engines running during summer etc so the less wieght ensures it heats up and becomes just as viscous as heavier hot oil... 40 or 50 weight is normally good for hot climates
like texas and some states during the summer
but normally 30 or 40 weight is average
u would use 20 weight in winter
maybe even 15 weight. All the information is online for you to find. Just use google.

10W-30

10W = How thick it is when it's cold..

30 = How thick it is when it's hot.

10W-30 would protect better when it's hot, like summer...
5W-30 would protect better when it's cold.. Like winter.. Or if you live in Antartica. Ha ha.

Lower the first number, thicker it is when it's been sitting there, so you get good amounts of start up protection.. When it gets hot, then the oil would be the second number, so it would protect while it's in the hot temperature range.. It's basically saying the temperature range that the oil will protect the engine for. That's all.

People might tell you to change oil when you enter Winter, but it's not much of a difference between 10w-30 and 5w-30, unless you live in huge temperature differences. As long as you don't get something like 85w-90 for your engine oil, you'll be fine.. Now the difference between conventional and full synthetic is a different story..

This post has been edited by Newbie: Jan 5, 2005 - 4:54 PM

how much performance gain would a full synthetic oil give? are there different viscosities?

i use 10w30 full synthetic

-forkee+Jan 5, 2005 - 10:28 PM

same here.

when i get an oil change (i need one) do i just tell them what i want or do i have to buy it and give it to them? is the full synthetic 10w30 better performance wise than normal oil? how much oil will i need?

Also depends on your mileage. IF you have high mileage start usings high mileage oil or synthetic. I use Mobil 1 synthetic and have been pleased. Just whatever you use, dont keep switching. Once you start using synthetic stay with it.

I wish everyone would realize that unless you have rebuilt the motor and prepped it for racing with looser clearances, you need the weight recommended in the owners manual.
Using a heavier oil can actually harm your car. it takes more horsepower to pump. it takes longer to get oil to everywhere in the mornings, it can cause your oil press relief in the filter to be operating all the time, thus NOT be filtering your oil,,, these are the main reasons you should stick with the 5w30 recommended in the book for MOST All driving conditions....and a multi-viscosity oil doesnt actually get thicker when its hot, it protects like an equivalent single weight oil at higher temps.
I have went to using the Amsoil series 2000 0W30 full synthetic, it works GREAT, oil light goes out instantly, no probs in hot or cold weather. recently did a trip to Dallas and Houston from KC, had some stretches where even the slow lane was cruising 85+ (2 hours at 4100 rpm!) 1500 miles round trip, used almost a half pint in 1500 miles of hard driving...