Should we be using lighter weight oil?

[Dave K.]

You can definately mix synthetic and regular oil.  The "gel" was caused by
something else.  I have switched on numerous cars/bikes without any
problems.  IF it really did cause a problem the oil companies would have
more than a few law suits on their hands.

Dave K.
'90 CQ - Castrol dino
'99 ML430 Mobil 1 0W-40
'94 Ducati 888 - Castrol Motorcycle synthetic
'70 Monte Carlo SS454 - 10W-40 Mobil 1


----- Original Message -----
From: "George Harris" <harchris at smokesignal.net>
To: <desmo888 at comcast.net>; <quattro at audifans.com>
Sent: Tuesday, December 31, 2002 10:38 AM
Subject: Re: Should we be using lighter weight oil?


> I believe that the viscosity rating on the can is at a specific
> temperature. In Greg's example he compared the oils at 5 deg. F. We know
> from the synthetic oil hoopla that the viscosity is more stable in
> synthetics so perhaps it doesn't thicken up as much as regular oil.
>
> Although one comment I have is to the fellow who mixes regular and
> synthetic; When I was considering changing my motorcycle to synthetic a
> knowledgeable fellow enthusiast told me to flush the engine with
> kerosene to get all the old oil out. He said that mixing the two would
> cause clotting. I witnessed this in another engine that wasn't cleaned
> out ... an oil passageway clogged with a thick gel of oil. Not pretty.
> Ever since I have been paranoid about mixing the two types.
>
> Cheers
> George
>
> "Dave K." wrote:
> >
> > What I can't understand is why a synthetic oil of the same viscosity
flows
> > more easily than a dino oil of the same viscosity at any given
temperature.
> > Viscosity IS flow, so what gives?
> >
> > Dave K.
> > '90 CQ
> >
> > ----- Original Message -----
> > From: "George Harris" <harchris at smokesignal.net>
> > To: <Greg.Roa at Cinergy.COM>; <quattro at audifans.com>
> > Sent: Monday, December 30, 2002 7:43 PM
> > Subject: RE: Should we be using lighter weight oil?
> >
> > > > That says it all for me.  I like numbers as much as the next
engineer,
> > but
> > > > a 5w rating doesn't mean much to me if my engine can't pump it in
the
> > morning.
> > >
> > > Aren't you comparing Apples (regular oil) and Oranges (synthetic)? Now
> > > try comparing the flow of 0W40 and 15W50 at the same temperature. In
my
> > > experience any oil, including the 10W50 synthetic that I use, is
pretty
> > > thin at operating temperatures. I think you want that flowability when
> > > you first start the car at 5 deg F.
> > >
> > > Cheers
> > > George