Are you sure of that? I had a Frontier and my reading of the maual
indicated that changing oil according to the "severe" scedule was open
to a broad interpertation.
Here is what was in my 2006 Frontier Owners Guide:
Operation under the following conditions may require more frequent oil
and filter changes:
* repeated short distance driving at cold outside temperatures
* driving in dusty conditions
* extensive idling
* towing a trailer
* stop and go commuting
Here is what the Nissan Maintenance Guide says:
Depending on your driving habits and local conditions, you should
follow one of the three maintenance schedules listed below. Use these
guidelines to determine which maintenance schedule to use:
PREMIUM MAINTENANCE* (Every 3,750 miles or 3 months, whichever comes
Premium Maintenance is a Nissanrecommended option that is suitable for
all driving habits and local conditions. Nissan developed Premium
Maintenance for owners who want the ultimate in preventative
maintenance. With Premium Maintenance, more maintenance items are
regularly checked or replaced than
with either Schedule 1 or Schedule 2 maintenance schedules.
Using the Premium Maintenance schedule may optimize the performance,
reliability, and resale value of your vehicle.
SCHEDULE 1 (Every 3,750 miles or 3 months, whichever comes first)
Schedule 1 features the same 3,750-mile service intervals as Premium
Maintenance; however, with Schedule 1 fewer maintenance items are
checked or replaced than with the Premium Maintenance schedule. Use
Schedule 1 if you primarily operate your vehicle under any of these
* Repeated short trips of less than 5 miles in normal temperatures or
less than 10 miles in freezing temperatures
* Stop-and-go traffic in hot weather or low-speed driving for long
* Driving in dusty conditions or on rough, muddy, or salt-spread roads
* Towing a trailer, or using a camper or car-top carrier
SCHEDULE 2 (Every 7,500 miles or 6 months, whichever comes first)
Schedule 2 features 7,500-mile service intervals; with Schedule 2
fewer maintenance items are regularly checked or replaced than with
Generally, Schedule 2 applies only to highway driving in temperate
conditions. Use Schedule 2 only if you primarily operate your vehicle
under conditions other than those listed in Schedule 1.
* Premium Maintenance is a Nissan-recommended option; however, owners
need not perform such maintenance in order to maintain the warranties
which come with their Nissan. Premium Maintenance may not be available
outside the United States, please inquire of your dealer.
It seems to me the wording is designed to encourage owners to use the
3,750 service interval, but really, how many people make repeated
short trips of less than 5 miles? My assumption would be if you do a
five mile commute, but still drive far enough at least weekly to warm
the car up, this short trip requirement wouldn't apply.
The stop and go driving requirement and low spped for long distance
requirements are undefined. I suppose if you live in LA, then you may
always be in stop and go traffic. While this might be hard on your
brakes, do you really think it is all that hard on the engine oil? I
suppose if you spend hours of time stopped and idling, then you need
to change your oil more often. This is where a system like the GM Oil
Monitor is very useful. It actually counts engine revolutions and
modifies oil change intervals accordingly.
I like the Ford descriptions of Normal and Severe Service better:
Determine which maintenance schedule to follow
It's important to follow the maintenance schedule that most closely
mirrors your driving habits and the conditions under which you drive.
For this reason, the Scheduled Maintenance Guide is divided into two
basic maintenance schedules: the Normal Schedule (further segmented
into Trucks, Fullsize Vans & SUVs and Cars & CUVs) and Special
Determining which maintenance schedule is right for you is easy. For
the most part, do you drive your Ford, Lincoln or Mercury vehicle
under typical, everyday conditions? If so, follow the Normal Schedule
Trucks, Fullsize Vans & SUVs, or Normal Schedule Cars & CUVs.
Special Operating Conditions
However, if one or more of the Special Operating Conditions outlined
below better describes how you typically operate your vehicle, you
will need to perform some maintenance services more often than the
Normal Schedule recommends.
. Towing a trailer or carrying heavy loads
. Extensive idling and/or driving at low-speeds for long distances
. Driving in dusty conditions
. Off-road operation
. Use of E85 fuel 50% of the time or greater (flex fuel vehicles only)
Important: For further details and information regarding these Special
Operating Conditions see page 42.
Items Needing Special Attention
If you operate your Ford/Lincoln/Mercury primarily in one of the more
demanding Special Operating Conditions listed below, you will need to
have some items maintained more frequently. If you only occasionally
operate your vehicle under these conditions, it is not necessary to
perform the additional maintenance. For specific recommendations, see
your Ford or Lincoln Mercury Dealership Service Advisor or Technician.
Notice the statements including the words "primarily" and
"occasionally." To me these implies most owners are exempt.
I think the systems like GM's (and others) that use oil life monitors
that adjust the change interval based on driving patterns are the
best. Toyota took an approach that at least eliminates confusion -
they did away with the whole normal/severe schedule confusion by just
saying to change the oil every 5000 miles. Of course all of this is
just for the US. In Europe oil change intervals are generally
specified to be much longer - even for Toyotas that use the same (?)
engines as US Toyotas. I have had people claim this is because
European specifications for oil are much better than in the US. Does
this mean if I use oil that meets the European specs, I could go even
The guys who write /Paradise Garage/ did a great study on this several
years ago. While aimed at GM 5.7L small-blocks (IIRC they did this with
a Firebird), they did a good job of combining theory with practice.
They also gathered some test data.
Here's the link: <
I've adopted some of their ideas for my 'vette and for a new 3.6L VVT-DI
engine. The only major change I've made was changing the filter more
frequently than I change the oil.
1. I use Synthetic Oil exclusively
2. I top up to the 'full' mark on the stick whenever it's about 1/2
3. I change when the oil life computer hits 30% or it's been 10K miles.
4. I change the filter every 5K (and top up to 'full')
I performed an arbitrary change on the VVT-DI engine when it turned 2500
miles. At that point, the oil life gauge was showing 72% -- I just
wanted to clear out excessive 'break-in uglies.'
Note -- neither of these engine types has a 'sludge' reputation so that
wasn't a consideration. That might be a consideration for Toyota
Maybe for people who own older Toyotas, but Toyota fixed whatever was
causing the problem with sludge. All of the Toyotas in my immeadiate
family (3 RAV4s, a Highlander, and a 4Runner) have the automatic
reminder that comes after 5000 miles, so I am not worried about
I have one of the Chrysler 2.7 engines in one of my 2 Concordes. They
are known for sludging up and catastrophically failing at between 60k
and 80k miles. Many people learned the hard way not to go by the
recommended 7500k change interval on those.
Of course it depends on the service that the vehicle sees too - i.e.,
lots of stop-and-go short-trip stuff vs. mostly highway use.
Mine has over 230k miles on it now and runs great because it is used on
my daily commute of 80 miles total each weekday and I change oil and
filter every 3000-3800 miles. Though people on the Chrysler forums will
insist that that engine will not last unless you use synthetic, I've
disproven that by using non-synth Castrol and 8 oz. of Marvel Mystery
Oil at all times.
There are definitely some engines that can tolerate abuse (long oil
change intervals), but some are definitely intolerant of that. I think
it has to do with the crankcase breathing design.
ALSO - I can't help but feel that a lot of instances of engines failing
due to sludging up is because more places (dealers included) than you
would think actually do not change the oil or filter when the customer
pays for it - I have seen that twice personally - once on my elderly
mother's car, and once on a Jeep that my daughter had bought that had
supposedly had oil and filter changed religiously every 3k miles at a
chain, and I proved that to be absolutely false.
(To reply by e-mail, replace the last letter of the alphabet in my
Yeah verily. One of the sludge issues was caused by dealers setting up
a stall aimed at just oil changes, sucking oil out with a small tube
inserted through the dip-stick sheath. That last pint never was drained.
Another issue not addressed in this thread is driving patterns. For a
few years I was overseas and my wife was driving my Pontiac with a 454.
All one or two mile trips. Engine never reached a proper operating
temperature. Car suffered with constant crankcase dilution (with the
oil level crawling UP the dipstick between changes. 3K wasn't often enough.
For cars with large engines and short trips, synthetic oil may be a
mistake since synthetics tend to be hygroscopic. A better choice is a
good petroleum based oil.
I'm sure that is true, but I was talking about an even worse scenario in
which the "what the customer doesn't know won't hurt them" (at least
until it's too late for it to be tracked back to us) philosophy of
business is in play and the customer is billed for the oil change that
is not performed. I caught the local Chrysler dealer at that when she
took he brand new Concorde in for its first oil and filter change. She
was charged for it, yet the original factory filter was on it (painted
flat black with "ORIGINAL FACTORY FILTER" paint stamped on it) and the
oil was exactly the same level and color as when she took it in.
There was another episode on a Jeep my daughter bought that was supposed
to have been "religiously" serviced (oil and filter changed every 3000
miles) for the previous owner at their local Amerilube (their next door
neighbor was the manager). Funny thing was that when I went to do the
first oil change on it, the filter on it was Mopar brand, and had heavy
rust all around the un-painted seam at its base.
(To reply by e-mail, replace the last letter of the alphabet in my
What did you do about it, Bill, and what was the result? This sort of
chicanery has been found at dealerships, quick change franchises, and
independent shops. I hope it isnt widespread, but it DOES happen.
In my mother's situation, I raised hell at the dealership. I did allow
them to do the oil and filter change along with an apology. I do all of
the work on my own cars, so it's not like I could tell them I wasn't
going to do business with them again. And when the opportunity arises
in the community, I tell them about what happened. For unrelated
reasons, my mother sold that car just a very few months later, so what
to do about her future oil changes became moot.
On the Jeep that my daughter bought, I let the previous owner know that
her wonderful next door neighbor that managed the neighborhood Amerilube
had been ripping her off for years and suggested that she check the
other vehicles she owned that had been serviced there. Of course she
could have been giving me a complete line of B.S. the whole time, but I
doubt a person lieing about it would have made up the bit about the next
door neighbor being the manager of the Amerilube that supposedly had
done all the oil/filter changes. If she was telling the truth,
hopefully the next door neighbor lost some business and reputation
(personal and business) over it.
(To reply by e-mail, replace the last letter of the alphabet in my
and there we have it folks - always check this stuff.
oils, especially conventionals, break down and start to lose their
ability to hold contaminants in suspension after a while - mostly as a
function of time and temperature. conventionals more quickly than
synthetics. this is why you /should/ check and change your oil.
but with monitoring and use of quality lubricants, you can safely use
significantly extended service intervals. i eat my own dogfood:
so fix the damned thing! that's not a function of temperature, that's a
function of excess fuel.
that's a bullshit underinformed differentiation. all modern motor oils
are detergent. it's the detergent that's hygroscopic, so you can't
besides, synthetics flow better when cold, thus they are a better
choice, not worse.
Flowing better at low temperatures is better, perhaps, IF you are subject
to low temperatures.. I, at this point, am not.
It is not necessarily the additive that is hygroscopic. Some synthetics
are more hygroscopic than hydrocarbon oils.
These are the glycol ester types of synthetics.
There is just no easy answer.
On 04/04/2010 09:37 AM, email@example.com wrote:
"esther" is a person's name. "ester" is a chemical compound group. but
you're right, it's glycol ethers that are brake fluids, not esters.
ester lubricants otoh are multitudinous. "glycol ester" is a ridiculous
On a carbureted engine with a choke it IS a function of t
emperature. If the engine (I think all 454 Pontiacs were
carbureted, by the way) is never warmed up the choke never comes off
and fuel dilution of the oil is a VERY REAL possibility.
Actually, synthetic oils, in general, DO tend to be more hygroscopic,
and provide less corrosion protection (marginally)
As for the synthetic flowing better when cold - most definitely - but
is that an advantage in Miami or SanDiego?
It is only an advantage if you NEED that cold flow advantage.
In Miami or San Diago the fact that it thins less with heat and is
generally more resistant to oxidation is more important.
On 04/03/2010 05:53 PM, firstname.lastname@example.org wrote:
so it's still advantageous!
besides, most engine wear occurs during warm-up. if a synthetic can
protect during this phase, and it can, then it's protecting the engine
more than a conventional oil.
Yes, but in the vast areas of North america where much below freezing
and much over 80F are rare, there is VERY little advantage. - and just
using a slightly heavier gerade oil for the warm temperatures does
virtually the same thing.
Except synthetic oils also tend (note, I said TEND - not necessarilly
always do) to drain down leaving less of a "static" oil film, they
NEED to get there quicker.
In real life, under "normal" conditions, there is almost un-measurable
difference in wear between standard dyno and normal synthetic lubs.
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