"top gear" wrote in message
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":::Jerry::::" wrote in message
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"Dave Plowman (News)" wrote in message
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snip

What I'm saying is that engines last longer and longer despite even
longer
oil change intervals. Ie, the makers know what they're talking about.
Both oils and engine manufacturing techniques - and or materials - are
improving all the time, so there really is no need to change oil more
frequently than the maker's recommendation.
snip

You have to remember that makers have extended the service intervals to
appeal to the 'Fleet' / contract hire market, they don't actually care
what
the mechanics are like post X [[1] mileage as the car will have gone
though
the auction market by then in most cases.

anything from 12k to 50k in most cases

Very good point and hit the target. I did point out that cars are designed
to have a life of 50K miles before harshness is apparent using average
grade
mineral oils. Use the best oils, full synthetics, in the engine and
transmission after run in, and change the transmission oil approx 20K
miles
then the newness feel and sound of the drivetrain will stay for most of
its
life. Service cost are designed to appeal to the company car market, who
ditch cars after 3 years maximum.

You are missing the point, the same can be true even if the recommended oils
and change periods are used, it is also true that engines and transmissions
can fail even if the best oils are used, life of components has far more to
do with how the car is driven than what oil might or might not have been
used - keep trying to 'crash' through the gears and any transmission will
have it's life expectancy shortened.

Rather than spend extra money on expensive 'snake oils' you are just as
likely to improve the life expectancy of engine components by using the
recommended oils and just change them more frequently. I don't agree that a
gearbox that has been treated with respect needs it's oil changed to a (so
called) higher spec', the biggest wear points in any gearbox are the syncro
cones and as they use friction to do their job no oil or additive is going
to help - indeed some oils or additives can make things worse and thus cause
far more wear in other parts of the gearbox due to people trying to force
the syncro cones to engage rather than slip past each other...

Service (mileage / time period) points were changed to save servicing cost,
not due to improved components / oils as their is far more to a proper
service than changing oils and filters.