I've suddenly realized it's been about a year since my last oil change.
Don't panic now, for almost three months of that time, my truck was
sitting on a ship, visiting parts of the world I'll never see.
The rest of the time it's done well less than 5,000 miles.
Problem is, due to circumstances beyond my control (including a probably
lack of compatible oil filters), oil won't get changed 'till end of
March. Probably have less than 100 more miles - we don't drive much, or
So, am I damaging my engine with old oil? Or is the # of miles more
Generally, mineral based (comes out of the ground) motor oil only lasts
about a year. Of course, all this depends on the type of oil, manufacturer,
etc. You don't say what it loks like, but if its relatively clean (not brown
or burnt) and feels good to the touch (slippery and not thin like water),
it'll go the 100 miles. They key here would be making sure that you have
good oil pressure when the engine is in use.
I suggest a good synthetic oil be used in your case. Synthetics don't have a
natural breakdown, and react well to long term storage.
Join www.devilbrad.com and find out what free exchange of info is all about.
I am not sure where you are getting your data but several factors are
involved in usefull oil life and regular motor oil can last for many
years on the shelve and has not automatic 1 year and its not good.
When it sits ina engine for a long period of time it can fall prey to
moisutre condensation from climate changes which will contaminate any
oil dino or SYN. SYN oil takes longer to break down for thermal and
shearing stress but they both get dirty. Generall if you do not drive
much you should change it at least once a year even if it is only 1000
miles and better still would be twice a year in the spring to remove
winter condensation and byproducts for cold starts and fall to have
fresh oil before cold winter sets in. Okay, let the trolls come out
and try to find fault here with this.
Showing up and baiting people is a good way to get blasted here but you know
that don't ya.
You only get jumped on when you post totally wrong and dangerous BS. Which
you do 99% of the time.
Although I don't agree with your opinion nobody will get killed over it. A
engine may wear quicker but with only 1000 miles a year the body will
probably fail first.
Oh, I liked 'cuda's new name for ya. Here's what it looks like.
What do ya think?
This is TOTAL crap...oil does not beakdown ever..Its the additives not
the oil. It last forever...
The concept that oil "breaks down" or "wears out" is not correct.
Just look at what has happened over the past fifteen years, in regards
to oil drain intervals. Fifteen years ago, typical recommended oil
drain intervals for a 300 horsepower H.D. diesel was around 8,000 to
10,000 miles in an over the road truck. Today, the same trucks
typically have 425 to 450 horsepower engines, yet the oil drain
intervals have increased to 15,000 to 25,000 miles. The same quality
crude oil base stocks that were used 15 years ago are used to make
oils of today. So why does the same oil today last twice as long as
it did fifteen years ago? The answer can be found within the additive
package of today's oil. The petroleum base of oil lube does not wear
out, rather it is the additives within the oil that become depleted,
due to the presence of contamination.
Oil last forever. It is the detergents in the oil that break down.
It the detergents that suspend the grime and dirt. Just like soap in
dishwater. The grease and dirt are still there but the detergent
suspended them. When this happens the dirt is no longer being washed
away from the wear points and is allowed to work on metal.
Moisture also gets into the oil. That will do damage in that it
separates the oil from itself. Myself it isn't the age you need worry
about but the moisture in the engine. Salt water air in the crank will
leave salt in the engine. Or if it was fresh water you still would
have moister. That will be mixed with the oil when you fire it up. If
you think I am full of it then just do the basic math. A oil change vs
a new engine. Why did you ask is cheap to be wrong.
As Max said, synthetic is your best option. As a side note ... you're
in Australia correct? (No shipping restrictions on auto-parts that
I'm aware of). I'd be happy to help you get the parts you need and
send them to you if that will help any. May cost a bit more with
shipping and all, but as has been said, better to be safe than sorry.
Suddenly, without warning, Craig C. exclaimed (27-Feb-07 12:46 AM):
Thanks for the offer, Craig, but that sort of thing I'd normally get
from PartsAmerica... 'cept I'll be in the US for a bit coming up, so I
can get the parts while I'm there. Gotta get some air filters too.
Planning on doing *lots* of shopping; the auto parts store is only the
tip of the iceberg. I love Australia but the shopping in this small
outback town gets very 'same old same old' very quickly :)
Incidentally, I'd already made the decision to go synthetic. With what
it costs for an oil change here, I'll probably save $$ in the long run :)
Used to do my own, but I forgot one slight factor when I bought this
truck: Arm length. Really hard to reach the filter! And before you
ask, hubby's not much taller than I :)
You might consider changing to the larger-style filter rather than the
typical shorty-style. Forgive the Fram part numbers here, but the
shorty-style filter that's normally specified is PH16.
The PH8 filter has the same threads, same O-ring, etc. -- but it has a
longer filter body and longer element.
Besides reducing restriction in the filter and a bit of a boost in pressure
to the bearings, it is a lot easier to grab a hold of since the filter body
sticks out a bit further from the mount.
A larger filter reduces oil pressure drop across the filter because it
presents more filter surface area to the oil flow. This is not so important
if the filter operates in bypass mode, but if it is used in full flow mode,
the pressure drop and flow restriction is very important.
On any vehicle where I've had an oil pressure gauge, you can easily see that
pressure is noticeably higher after the switch to the longer filter. Since
the sending unit is in the circuit after the filter, it's showing an
increase due to the less restrictive filter. I'm not an engineer, so I
wouldn't know whether the engine actually derives real benefit from any
additional pressure over the standard pressure.
The big difference is that the oil filter is much easier to install and
You're not at Harold E. Holt, Exmouth, Western Australia by any chance
I was stationed there for two years, 1981 and 1982.
I loved that place! Diving, fishing and camping were the ticket! I had
a Ford F150 there at the time. I put oil and filters in the cab so
they'd be there when my truck arrived.
Only owned Dodge trucks since....:)
There are 2 killers of lube oil. The first is water though condensation.
This will combine with the oil's residual sulpher and create sulpreric acid,
which corrodes the oil. The second is heat. The lubricity of oil falls
dramatically when the oil exceeds 100c. Exposure to these high temperatures
causes the oil's surface tension to increase, a loss of shear strength along
with viscosity. The first problem will be a non-issue in a desert
environment, but the second could be. An oil cooler will greatly enhance the
life of your oil, provided flow through the cooler is controlled with a 90c
You will be OK. When you do drive it however, just make sure to drive it
long enough to reach operating temp for a while. The short trips don't get
the engine hot enough to cook out the moisture. If you used a good quality
oil on your last change, you'll be OK. Most modern oils have enough
additives to keep your TBN within an acceptable range, even after a year.
Just don't let it happen again!..... tsk... tsk.... tsk
Suddenly, without warning, Mike Simmons exclaimed (27-Feb-07 11:00 AM):
Problem is, there's nowhere to *go*. Town's only a couple of miles
across (my longest round trip is just over 6 miles), and the next
nearest town (I'm really not kidding here) is, I think, about 300 miles
away. So, I either head outback, or I drive around town in circles :)
Too bloody hot to go outback just now...
That's my excuse for no oil change. There's no concept here about
"while you wait". I'd have to leave the truck, and ride my mountain
bike back from the shop. Dammit, it's 100 degrees out there!
(get a blowdryer. Put it on high. Point it at your face. While
exercising. THATS what I'm talking about!)
Which is why the synthetic. Once a year, in winter :)
Suddenly, without warning, jmc exclaimed (26-Feb-07 9:22 PM):
Ok, so I'm online buying some filters (prolly can't get them here). Am
I ripping myself off by buying the Fram ToughGuard filters, rather than
the regular ones. My driving here meets some of the types of driving in
the ad: Extreme heat & Unusually dirty roads (weird statement but I'll
be driving some hundreds of miles of very dusty 4x4 roads in a couple of
months... and many roads around here are unpaved, anyway.
Anyway, I'll get a few now, and gather the collective wisdom of this
group for when I need to buy the next batch :)
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