Single & Multiple Viscosity Oil

[TheCarNutz@xxxxxxx]

In a message dated 1/11/02 1:03:36 PM Pacific Standard Time, 
dardal@xxxxxxxxxxxxxxx writes:

> I doubt it will make much difference now, but you should avoid using single 
>  weight oils.  A 10w30 or 20w40 is much better than 30w or 40w.  Even if 
the 
>  car was built at a time when these oils were recommended, the times have 
>  changed and the oils are so much better now...
>  D^2
I'm a bit puzzled when someone makes a statement, as if there is a "chemical" 
difference between single weight and multiple viscosity oils.  If you look at 
the top of the can and the ratings are the same for both, the only difference 
is in cold weather climates you should use multiple viscosity oils in the 
winter, since when cold they are the 10w as in 10w30, and when warmed up are 
the 30 as in 10w30.  In otherwords, thin to provide proper lubrication when 
cold, and thicker after warmup.  If you lived in a desert climate as I and 
some other list members, use of single 30 or 40W viscosity oil in the summer 
is quite common due to the intense heat.  The quality of the oil is the same 
in both cases.
                                        Bill B.