Synthetic oil in an 850 with 150K miles

I have a 1995 850 wagon with about 160K miles. At about 150K miles, a
mechanic in a local repair shop recommended I switch to synthetic oil
because of the age and mileage on the vehicle. I did start to use synthetic
and have since change the oil 3 times (i.e. every 3000 miles). I now see
oil stains on the garage floor. Several thread in this newsgroup mention
that synthetic oil can cause leaks in older cars. If the synthetic oil is
causing my apparent leak, will changing back to regular oil stop the leak?

What is it about synthetic that causes the leak in older cars?

 

It's the high-detergent action, which dissolves varnish and
sludge on seals, and sometimes the seals themselves, if the
rubber isn't compatible. The usual approach is to replace all the
affected seals, but you could try removing the synthetic oil and
switching to 'high mileage' oil, which will cause the seals to
swell. This may or may not fix the problem, but if it does it
probably won't be a permanent fix. If you plan to keep the car,
then since the damage is already done you may want to spring for
new oil seals and then keep using synthetic - it should prevent
the lifters from sticking, anyway.

 

Go back to conventional oil, preferably one of the high mileage
formulations like Valvoline MaxLife, Castrol High Mileage, etc.

I used to think that this was an old wives tale, but I have seen the
problem myself when trying to put synthetic oils, especially Mobil-1,
into older vehicles.

John

 

Synthetic oil is an excellent way for the poor (ha ha) oil companies to
extract money from our fat (ha ha) wallets. There is no documented
evidence that cars that use it have any better reliability. Sure it is
better, but replacing all the copper wiring with gold is better also.
But the bottom line is are there any real benefits. So far there are
none and as has been mentioned here there are many problems. Following
the manufacturers recommendations is all that is necessary, in fact is
more than necessary.

 

I would be interrested in your data source used for this conclusion. I
would have thought that the higher "breakdown temperature" of synthetic oil
would have been particularly beneficial for turbos, as the oil would not
tend to coke on the high speed - high temperature bearings.

Thanks in advance for any data sources you can provide.

 

You missed the point of my post. Synthetic oil is sold on the basis of
laboratory tests. It is never sold on the basis of real world use in
cars. Sure people say that they used it and had no problems, but I can
say that about using the factory recommended oils, filters and changes.
The truth is there is no field data supporting the use of synthetic oil
based upon and A/B comparison with manufacturer recommended maintenance.
None. If they had it they would use it unless it wasn't favorable.

If you don't want oil to coke, then use non-coking oil like used in
motorcycles. Cars don't need it. I use it in my garden tractor since,
like a motorcycle, it is an air cooled engine. If I don't use
non-coking oil in my garden tractor, the oil is like tar when I drain it.

 

You want some real-world support? I am the original owner of
a 1986 Honda Civic Si. This 1.5 liter engine, and the one after it,
both have a reputation for starting to burn serious oil after
about 120k miles, even with regular valve adjustment. I've run it
mostly on synthetic since it was broken in, and while I get a
puff of blue smoke from draindown past the valve seals if I let
it sit for a few days, it doesn't use an appreciable amount of
oil, and doesn't produce blue smoke while running. It has about
143k miles on it. Not enough? I also have an '81 Suzuki GS850
that I've owned since '89, and I use full synthetic in that.
Aside from doing a gasket replacement because of weeping (not
seriously leaking) oil about 15 years ago, the bike also uses no
oil at 25 years old and 26k miles. Both engines have been run
very hard on occasion, although not that much in later years.

I'm hardly a die-hard synthetic oil fan, especially for Volvo
Red Block engines - I usually tell people to avoid it. But that
isn't the same as saying that it has no benefits when used from
the beginning.

 

If you have cleaned a number of oil drain pipes from turbos, then you
appreciate the difference between synthetic and regular oils.

Jens

 

I started using synthetic oil in my wifes car at 187.000klm in mine
at 135.000 klm neither use oil or leak oil both ar turbos My sons car using
dino oil doesnt leak at 301.000klm all are red block engines Volvos .

 

These are anecdotal stories and don't prove a thing. I drive my Volvos
175,000 mile now and never have a puff of smoke or any oil usage and I
just use the Volvo recommended oils, filters, and intervals (which are
7,500 miles and 10,000 miles. But neither of us is proving anything.

A laboratory comparison would take identical vehicles and run them to
death under identical conditions using the recommended changes and
filters. This would prove something, but anecdotal stories are just
that. In order to justify the use of synthetic oil, it needs to either
provide longer engine life or provide the same engine life with extended
change intervals. It has not been shown to do either.

 

Personally I am sold on synthetics for turbo charged cars, cars which
see very cold temperatures and cars which see very high temperatures.
Also for engine designs where sludge has been an issue such as certain
Toyotas.

John

 

Not to nitpick, but what would be better about gold wiring?

 

Because of its high electrical conductivity and resistance to corrosion
and other desirable combinations of physical and chemical properties,
gold emerged in the late 20th century as an essential industrial metal,
particularly as a thin plating on electrical card contacts and
connectors. Relays that are for high currents have silver contacts and
those for low voltages have gold contacts. Many micro-chips use gold
internal wiring for its conductivity on very small cross-sections. The
most common choices are aluminum and gold and gold is superior.

Electrical resistivity are room temperature:

Aluminum: 26.50 nano-ohms per meter
Gold: 22.14 nano-ohms per meter
Copper: 16.78 nano-ohms per meter
Silver: 15.87 nano-ohms per meter


So for precise instruments, gold is superior because of its very low
contact resistance.

For high current applications, silver is superior because of its high
conductivity and moderate contact resistance.

Copper and aluminum are not useable unless the connectors are exotic
(not copper or aluminum) or the ends are plated. We all know about the
problems of aluminum house wiring and copper is not a lot better.

If you are using synthetic oil on an engine designed for conventional
oil, you are changing the operation of the engine. Synthetic oils have
smaller molecules than conventional motor oils. This means that it is
not compatible with some engine designs. If the manufacturer doesn't
recommend it, you use it at your own risk. If engines last perfectly
well with conventional oil, there is no incentive to take this risk.

 

-----------snip ------------------
igns. If the manufacturer doesn't

Hi all,

I've found this thread to be very interesting.

For the sake of argument, lets say that one has been using a blend in an
older engine. What are the pros & cons of going back to a conventional
oil ?

Thanks,

Perk >)

 

The only pros are lower cost and less chance of leaks
developing in the future. The risk of leaks depends on how
long you're been using synthetic or syn blend; if a short
time, then the risk of leaks developing is higher than if
you've been using it for years.

 

So who here has had a B230F fail yet after regular oil maintenance with
a synthetic?

 

Well presented - I'll give you that, but it does not establish a case
for the use of gold wires! Contacts, yes, wires - copper is far better,
cheaper and lighter, as your own numbers amply demonstrate!

Cheers.

Greg

 

Unfortunately, that won't prove anything.

There's good evidence that synthetic oil is superior to conventional oil
in some ways. But what Stephen has been saying (I think) is that no-one
has proved that these properties lead to longer engine life, on average,
than conventional oil would in the same make of engine under identical
usage conditions. As far as I know, no such tests have been done . . .
but if they have, I hope someone will post a link or reference.

Rick

 

Espressopithecus (Java Man) wrote:
]

In other words, no! You don't know anyone who reports increased engine
wear or decreased life using synthetic oil!

It does prove something -- it proves you are making conjectures without
data!

 

The pro is saving money. As far as the cons, who knows. Synthetic
blend is really a poorly defined term and many "conventional" oils could
call themselves a blend if they wanted to. In fact, the Connoco line of
oils (sold as Union 76, Phillips 66, Connoco and Motorcraft) are all
labeled synthetic blend.

John