Quote:
Originally posted by Azal Khan:
What are the proper viscosities? I heward that 10w40 can be used in all climates...What should I use when the avg. temp is 20 degrees in the winter season?....I have been using 10w30 all season....is that bad?
0-30 is the best, 5-30 is second best. The first number is cold viscocity while the 2nd number is operating temp viscocity.

The kicker is that a 0w at 70F is still thicker than the 30w at engine temp. 5W is a lil worse, and 10W even worse than that. This is compounded even worse in cold weather.

Being that about 80% of engine wear occurs at startup you want the oil that starts flowing the fastest. Which is 0-30W.

So, even though I'm on the coast of Cali, I use 0-30W.

Now for anything ending in a 40W, Don't use it, it's thicker than nissan designed and won't get into the smaller places to lube as easily.
-Chris
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