Hi Glen:
I agree that reasonably close attention must be paid to viscosity but let's
not forget the reason for the prescribed oils being chosen. It has
everything to do with availability of suitable lubricants when the engine
was designed and we know that many of our LBC engines were designed before
most of us were born - even me.
The whole thick oil thing harkens back to the early days of the automobile
and the inferior lubricants available. There should be nothing really
wrong with a 0 - 50 oil. It works as a 0 when cold and a 50 when hot and
is really somewhat equivalent to the 20-50 or straight 30 called for by the
factory. The biggest reason for the heavy oils in Brit motors (my AJS
motorcycle engine uses single weight 50) is the tremendous fear of a hot,
hardworking engine being destroyed by old fashioned oils which could not
maintain viscosity when hot. Synthetics are affected very slightly by heat
and don't lose that vital viscosity index when it is most needed.
The major benefit of synthetics is viscosity control. Oils with cold
starting fluidity and consistent high temperature viscosity are vital
protectors of engines of all kinds and ages. Synthetics provide this
protection. Add to this their resistance to breakdown, their inability to
form wax and sludge, and their resistance to the formation of acids,and we
have the ideal lubricant for any engine - unless the engine is too far gone
to benefit.
Jonmac has a point. If the prices he quoted are true, the Brits, as
usual, are still being seriously ripped off on the price of things
automotive. I pay $7.00 per litre for Mobil 1here in Alberta, which equals
about $4.00 US per US qt or around #3 per litre. The figures he is quoting
are certainly enough to scare your basic frugal Brit back into using
re-cycled oil. He is paying #7 per litre which is an increase over my
price of about 230%. Somebody's getting rich and it isn't the car driver.
Note that we import Mobil 1 from the US - I have no idea what it normally
sells for there. What about it Glen?
>John,
>
>I suspect that many people switching to synthetics may be going from 20W50
>to something like 5W50 and that can't be kosher, synthetic or not.
>
>Glen
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