Earle Horton wrote:
> My owner's manual (1995 YJ) says to "Select oil viscosity according
> to the lowest air temperature expected before the next oil change
> using the engine oil viscosity chart". According to the chart, 5W30
> is good up to a "lowest air temperature expected" of 60º, and 10W30
> is good down to 0º! There is considerable overlap there. According
> to this information, I could probably get away with either 5W30 or
> 10W30 year round, living where I live.
>
> It's not just easier starts. An oil that is too heavy can cause
> increased wear during cold starts, because it doesn't get to the
> bearings fast enough. Gene Berg said that "the heavier the oil, the
> less it lubricates" http://www.geneberg.com/article.php?ArticleID=237
> third paragraph. Ignore the part about clamping a cow magnet to the
> outside of your oil pickup tube. ;^)

I put a couple of hard-drive magnets on the oil filter. Figure it
won't hurt anthing and if it picks up some metal that's good too.

> Like you, I would probably have chosen 10W30 for an oil change in
> August, but this little misunderstanding won't hurt anything.

That's my feeling. Maby they will send me up to Peterson AFB this winter.

--
DougW