YACT: Girl at my work has not changed her oil in 36,000 miles =(

Red

Diamond Member
Aug 22, 2002
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So I was chatting about cars with this girl at work yesterday. She is about 23 years old and drives a 97 Tacoma. I was telling her about how I changed my oil the day before with Mobil 1 Synthetic and I need to change the oil every 3,750 miles to keep my extended warranty valid. Then she says "geez, I need to get my oil changed in my truck."

And I asked her when she last got it changed...

"Well, my sticker from Valvoline says I needed to get it changed at 77,630 miles..."

I asked her how many miles she has now.

"I just rolled over 124,000. Funny thing is, my check engine light came on last week and it made me look at the oil change sticker to see when I needed it done. LOLZ"

I'll post the VIN number so you guys know what to avoid.
 

cronos

Diamond Member
Nov 7, 2001
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she might have driven the car the past 20,000 miles without oil.
damn.
 

Vette73

Lifer
Jul 5, 2000
21,503
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I have had customers do thing slike that all the time then they wonder why their gaskets leak, engines eat oil, etc...

One girl told me she does not need her oil changed as the Chevy Cav can go 100K before its first "Tune-Up" :Q
Needless to say that car has not held up well the last time I saw it.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
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Originally posted by: saxguy
she might have driven the car the past 20,000 miles without oil.
damn.
The car wouldn't go 2,000 miles with no oil. It wouldn't even go 200 miles.

GAH! :|

See my post in the "Audi dealership" thread.

People that don't take care of their automobiles anger me.

Her engine is ruined for all intents and purposes. She easily put 100,000 miles of wear on it during the last 35,000 miles.

Her oil filter would've saturated some 25,000 miles ago, so she has been running unfiltered oil.

Further, I would be willing to bet that her air filter is probably in need of service too. Poor combustion efficiency is just that much harder on your oil.

Ugh. She ruined her car because of her astounding stupdity and lazyness.

May the AutoGod have mercy on her soul.. lol
 

Hammer

Lifer
Oct 19, 2001
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you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?
 

Red

Diamond Member
Aug 22, 2002
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Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
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Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?
As he should be.

It's the "severe service" schedule for most automobiles. Nearly all driving is severe service.

To elaborate, your oil filter is about 50% of the "life" of an oil. You usually need to change your oil because of your oil filter, not because of your oil. This is especually true with synthetics.

Mobil1 synthetic isn't anything special. It should be treated like conventional oil.
 

Caveman

Platinum Member
Nov 18, 1999
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A quick google for Amsoil synthestic will show you that you can easily get 25k without a change within that oill... In fact, it really never "breaks down, it has more to do with water collection, etc...

Recommended procedure is filter change at 12.5 K with a oil change at 25K
 

Turkish

Lifer
May 26, 2003
15,547
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Originally posted by: Red
Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
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Originally posted by: Hammer
i have a full synthetic in mine, but the oil changes average around 10-12k miles.
You are potentially doing your automobile's engine a great disservice. 12k is too long without oil analysis. Period.

It depends on how good the synthetic you're running is, and how good your oil filter is. If it is a small, low grade filter, it could be becomming saturated after 5,000-7,000 miles or so. This is especially true if you have a K&N air filter. A saturated, bypassing filter is worthless.. obviously.

Even if your manual calls for 10k changes, that is ONLY under extremely LIGHT duty. Light duty does NOT mean short trips.

90% of all driving is "severe service". Inside an engine isn't the friendliest of places.

Unless 90% of your driving is highway, you never run your engine for less than 25 minutes, it is around 70F day and night where you live, and you have a very light foot.. I suggest you reevaluate your maintenance pracitices if you care about the longevity of your automobile's engine.
Originally posted by: Xiety

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?
Just means regular conventional "made from dinosaur juice" oil.

Nothing inheirently wrong with Mobil1 5W-30, but depending on where you live, Mobil1 10W-30 may be more appropriate. It has slightly better specs.
Originally posted by: Caveman
A quick google for Amsoil synthestic will show you that you can easily get 25k without a change within that oill... In fact, it really never "breaks down, it has more to do with water collection, etc...

Recommended procedure is filter change at 12.5 K with a oil change at 25K
ONLY if you are using an AMSOil oil filter can you change it at 12k miles.

NEVER go 25,000 miles without oil analysis. The oil does absolutely not "never break down". Premium synthetics are formulated with very robust additive packages. That is why they can potentially go so long. The additives are still used up as the oil is used. They just have more of them.
 

Red

Diamond Member
Aug 22, 2002
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Originally posted by: Xiety
Originally posted by: Red
Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?

It's oil. It's synthetic so it has better specs than a conventional dino oil. Dino oil is "dinosaur oil" ... just regular oil that hasn't been processed like synthetic oils. Dino is cheaper and has lower specs while synthetic is the opposite.
 

Calin

Diamond Member
Apr 9, 2001
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I remember the story about some Citroen 2CV that was driver 70 000km with the original oil.
And some other story about another Citroen 2CV that was driven 50 000km in the first gear :p

Calin
 

PlatinumGold

Lifer
Aug 11, 2000
23,168
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71
Originally posted by: Xiety
Originally posted by: Red
Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?


dino = dinosour, as in stuff that comes out of the ground vs synthetic.
 

Caveman

Platinum Member
Nov 18, 1999
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See Bolded Text

Oil Filter Changes At Six Month Intervals
Q. Why does AMSOIL say to change the AMSOIL SDF Oil Filter at six months regardless of the mileage.. I have only gone 5,000 miles and figure that I could go the whole year without changing it and be good.

A. Once an engine is run with new oil, byproducts of combustion are introduced into the oil. These byproducts are harmful chemicals that continue to degrade the integrity of the motor oil as well as the oil filter media even though the engine may be off. This is why a time limit is published as well as mileage. Short trip driving can be just as detrimental to motor oil and filters as high mileage use, and even more so in some cases. It?s possible that the oil is still intact at the end of the published time limit, but oil analysis would be needed to verify this. Heavy trucks use this practice regularly, however in small sump capacity engines, the cost of the test is nearly as much as the cost of an oil change



Series 2000 Synthetic 0W-30 Motor Oil
Race-proven technology designed for passenger car performance. Provides unsurpassed fuel efficiency and up to twice the wear protection provided by popular conventional and synthetic motor oils. Recommended for use in all vehicles requiring 5W-20, 5W-30 or 10W-30 motor oils. Product Code: TSO




AMSOIL Series 2000 Synthetic 0W-30 Motor Oil is Recommended for Applications Requiring the Following Specifications:

API SL, SH, SJ, CF
ILSAC GF-1, GF-2, GF-3
ACEA A-1, A-2, A-3, B-1, B-2
Chrysler MS-6395 H
Ford ESE M2C-153G
GM 4718M, 6094M
US MIL L-46167B
VW 505.00, 501.00
Mercedes Benz AG 226.1
JASO VTW Spec.
Product Description

Passenger car and light-truck engines today are built for fuel efficiency and power. AMSOIL Series 2000 Synthetic 0W-30 Motor Oil optimizes efficiency and power without the sacrifice in wear protection that comes with many fuel-efficient, low-viscosity oils.

Testing shows AMSOIL Series 2000 Synthetic 0W-30 Motor Oil dramatically outperforms popular conventional and synthetic motor oils of much higher viscosity in wear protection (see chart).

Fuel Efficient Formula

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil efficiently transfers energy from the engine to the drivetrain. Its low coefficient of friction inhibits the energy loss to "drag" common to high viscosity oils.

Motorists seeking the ultimate in fuel efficiency may use AMSOIL Series 2000 Synthetic 0W-30 Motor Oil in place of higher viscosity motor oils.

High Temperature Protection

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil protects in high temperatures better than do the high-viscosity conventional and synthetic oils tested (see chart). Even after extended service in the engine, Series 2000 Synthetic 0W-30 Motor Oil maintains its ability to protect in high temperatures.

Low Temperature Protection

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil is specially formulated for superior cold temperature engine protection. Series 2000 retains excellent fluidity in extremely low temperatures, so it flows quickly and reliably to allow easy starting and immediate lubricating protection.

Motorists seeking cold temperature dependability and protection may use AMSOIL Series 2000 Synthetic 0W-30 Motor Oil in place of higher viscosity motor oils.

Heat Stability

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil is highly resistant to volatility. For example, in heat that causes conventional motor oils to lose as much as 25 percent of their mass, AMSOIL Series 2000 Synthetic 0W-30 Motor Oil loses less than ten percent.

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil's resistance to volatility keeps oil consumption extremely low and, more importantly, keeps the engine thoroughly lubricated and protected. Its resistance to volatility also helps keep fuel efficiency high and emissions low.

Clean Engine Formula

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil remains free of sludge, varnish and other by-products of high temperature degradation. With no deposits to foul them, engines stay cleaner longer for top performance and efficiency and maximum service life.

Shear Stability

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil is highly shear-resistant. With AMSOIL Series 2000 Synthetic 0W-30 Motor Oil's excellent viscosity retention, the protection that goes into the engine is the protection that stays in the engine, even over an extended course of severe service.

MIXING AMSOIL

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil may be mixed with petroleum-based oils or other synthetic oils. However, a mixture of AMSOIL Series 2000 Synthetic 0W-30 Motor Oil and another oil may offer a shorter service life than pure AMSOIL Series 2000 Synthetic 0W-30 Motor Oil does.

SERVICE LIFE

In personal cars and light-duty trucks with non-turbocharged gasoline engines: change the oil at 35,000-mile or one-year intervals, whichever comes first.

In turbocharged gasoline engines and occasionally used gasoline engines: change the oil at intervals up to three times longer recommended by the engine manufacturer or six months, whichever comes first.

In high performance and racing engines: specified by Owner Experience/Oil Analysis.

Marine four-cycle gasoline engines and infrequently used automotive four-cycle gasoline engines: drain oil at intervals up to three times longer than those recommended by the engine manufacturer, or one year, whichever comes first.

In fleet and industrial engines: drain oil at intervals up to two times longer than recommended by the manufacturer, or six months, whichever comes first.

AMSOIL Oil Filters should be changed at 12,500-mile or six-month intervals (whichever comes first) in gasoline engines. If a Hastings or other filter is used, filter should be changed at manufacturer's recommendation.

TYPICAL PHYSICAL PROPERTIES (revised 03/03)

AMSOIL Series 2000 Synthetic 0W-30 Motor Oil (TSO)

Kinematic Viscosity @ 100°C, cSt (ASTM D-445)
11.2

Kinematic Viscosity @ 40°C, cSt (ASTM D-445)
56.9

Viscosity Index (ASTM D-2270)
195

Cold Crank Simulator Apparent Viscosity @ -35°C, cP (ASTM D 2602)
5520

Borderline Pumping Temperature °C (°F) (ASTM D3829) -40 (-40)

Pour Point °C (°F) (ASTM D 92)
-54 (-65)

Flash Point °C (°F) (ASTM D 92)
226 (439)

Fire Point °C (°F) (ASTM D 92) 247 (477)

Noack Volatility (DIN 51581) 250°C for 1 hour, % weight loss 8.6

High Temperature/High Shear Viscosity cP, X°C, X s-1 (ASTM D4683) 3.4

Four-Ball Wear Test (ASTM D 4172: 40kgf, 150°C, 1800 rpm, 1 hr) Scar diameter, mm 0.374

Total Base Number
>11.0
 

Hammer

Lifer
Oct 19, 2001
13,217
1
81
Originally posted by: Eli
Originally posted by: Hammer
i have a full synthetic in mine, but the oil changes average around 10-12k miles.
You are potentially doing your automobile's engine a great disservice. 12k is too long without oil analysis. Period.

i seriously doubt i'm damaging the car as that is what is recommended for my car. it has a sensor in it that tells me when i need to take it in for oil service. all my maintenance has been on time and my car is in great shape.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
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Originally posted by: Red
Originally posted by: Xiety
Originally posted by: Red
Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?

It's oil. It's synthetic so it has better specs than a conventional dino oil. Dino oil is "dinosaur oil" ... just regular oil that hasn't been processed like synthetic oils. Dino is cheaper and has lower specs while synthetic is the opposite.
gah, misinformation!

Just because it is synthetic does not mean it is better.

For example, there are 10 petroleum convention oils that are better than Wal-Mart SuperTech FullSyn 10W-30(Worst to best); Havoline Petroleum, Chevron Supreme, Pennzoil LongLife HD, 76 Lubricants Guardol QLT, Mobil Delvac 1300 Super, Texaco URSA Premium TDX, Chevron Delo 400, 76 Lubricants Nascar HP, Precision 102P, and Citgo Citgard 600.

;)
Originally posted by: Hammer
Originally posted by: Eli
Originally posted by: Hammer
i have a full synthetic in mine, but the oil changes average around 10-12k miles.
You are potentially doing your automobile's engine a great disservice. 12k is too long without oil analysis. Period.

i seriously doubt i'm damaging the car as that is what is recommended for my car. it has a sensor in it that tells me when i need to take it in for oil service. all my maintenance has been on time and my car is in great shape.
There is no sensor that can tell you when your oil needs to be changed.

They're getting more advanced, ie: calculating it based on more and more operating conditions, but there are still variables that it does not take into account, like the size and quality of your oil and oil filter, environmental conditions like heat, cold and dust, etc.

12,000 miles is too long, unless you are truely light duty service. If you take frequent short trips, drive in city traffic, or have a K&N air filter, I can guarentee you that you are wearing your engine faster than you could be.

Of course, if that means only 200,000 miles instead of 250,000.. that may not matter to you.
 

Caveman

Platinum Member
Nov 18, 1999
2,532
34
91
Folks... do some reading about synythetic oils if you think that 12k is too long to go without a change. Please read my cut and past from the Amsoil website...

Comparing synthetic oil to standard oil is comparing apples and oranges... Though I agree that all synthetic oils are not created equal!

The reason you don't change trans fluid every 5k is because it's not *designed* to be changed that often. Obviously, you won't damage your car by changing it more often but what's the sense in doing something "out of spec"?

The same goes for synthetic oil... It has a purpose and that purpose is to be able to run a high quality lube in your car for extended periods...
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
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Originally posted by: Caveman
See Bolded Text
<snip>
I am very familiar with AMSOil oils and their recommendations. :p

They do NOT guarentee their oil to last 25,000 miles unless you are running oil analysis.

I repeat. DO NOT run ANY oil for 25,000 miles unless you are running oil analysis. There is far more to oil life than the oil itself.
Originally posted by: Caveman
Folks... do some reading about synythetic oils if you think that 12k is too long to go without a change. Please read my cut and past from the Amsoil website...

Comparing synthetic oil to standard oil is comparing apples and oranges... Though I agree that all synthetic oils are not created equal!

The reason you don't change trans fluid every 5k is because it's not *designed* to be changed that often. Obviously, you won't damage your car by changing it more often but what's the sense in doing something "out of spec"?

The same goes for synthetic oil... It has a purpose and that purpose is to be able to run a high quality lube in your car for extended periods...
No. The reason you don't change tranny fluid every 5k is because it isn't exposed to corrosive combustion byproducts, dirt, water, soot, carbon, etc.

Besides, AMSOil is an ultra-premium synthetic. You absolutely cannot compare it to the likes of something like Mobil1. That's where the apples and oranges are here.
 

Caveman

Platinum Member
Nov 18, 1999
2,532
34
91
Eli...

I agree that not doing an oil analysis is not a "good idea". But... running the analysis is not something that's done *because* you are running synthetic. You really should do the same thing running traditional oil as a 3.5K interval is roughly equivalent to a 35K interval. The bottom line is that if you've got oil problems (no matter what oil you're using) you have ENGINE problems. It's just better to "catch these problems" in intervals greater than 35K.

BUT...

Think about this... NOBODY that uses organic oil ever does these test and thus will never know if there is premature rig/piston/head wear, etc...

As a mechanical engineer, my opinion is that it's really just a CYA manuever by AMSOIL to avoid lawsuits and make them some extra $$.

I'd feel more comfortable running AMSOIL for 25K without tests than organic oil for 3.5K without test...
 

Hammer

Lifer
Oct 19, 2001
13,217
1
81
Originally posted by: Eli
Originally posted by: Red
Originally posted by: Xiety
Originally posted by: Red
Originally posted by: Hammer
you changed your oil every 3750 miles and you use a full sythentic? what kind of car do you drive?

'97 I30. I realize synthetic is overkill, I'm justing using some 5W-30 Mobile 1 that I've had sitting around for a while. As soon as I run out I'll be using dino =)

What is dino? I am the OP of the Audi dealership thread and saw it in there a couple times too, so I guess I would ask here?

BTW, I use Mobil 5W-30 as well, why are you giving up on it? Not a good oil?

It's oil. It's synthetic so it has better specs than a conventional dino oil. Dino oil is "dinosaur oil" ... just regular oil that hasn't been processed like synthetic oils. Dino is cheaper and has lower specs while synthetic is the opposite.
gah, misinformation!

Just because it is synthetic does not mean it is better.

For example, there are 10 petroleum convention oils that are better than Wal-Mart SuperTech FullSyn 10W-30(Worst to best); Havoline Petroleum, Chevron Supreme, Pennzoil LongLife HD, 76 Lubricants Guardol QLT, Mobil Delvac 1300 Super, Texaco URSA Premium TDX, Chevron Delo 400, 76 Lubricants Nascar HP, Precision 102P, and Citgo Citgard 600.

;)
Originally posted by: Hammer
Originally posted by: Eli
Originally posted by: Hammer
i have a full synthetic in mine, but the oil changes average around 10-12k miles.
You are potentially doing your automobile's engine a great disservice. 12k is too long without oil analysis. Period.

i seriously doubt i'm damaging the car as that is what is recommended for my car. it has a sensor in it that tells me when i need to take it in for oil service. all my maintenance has been on time and my car is in great shape.
There is no sensor that can tell you when your oil needs to be changed.

They're getting more advanced, ie: calculating it based on more and more operating conditions, but there are still variables that it does not take into account, like the size and quality of your oil and oil filter, environmental conditions like heat, cold and dust, etc.

12,000 miles is too long, unless you are truely light duty service. If you take frequent short trips, drive in city traffic, or have a K&amp;N air filter, I can guarentee you that you are wearing your engine faster than you could be.

Of course, if that means only 200,000 miles instead of 250,000.. that may not matter to you.

i think i'll stick with what BMW says since that seems to be working so far.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
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Originally posted by: Caveman
Eli...

I agree that not doing an oil analysis is not a "good idea". But... running the analysis is not something that's done *because* you are running synthetic. You really should do the same thing running traditional oil as a 3.5K interval is roughly equivalent to a 35K interval. The bottom line is that if you've got oil problems (no matter what oil you're using) you have ENGINE problems. It's just better to "catch these problems" in intervals greater than 35K.

BUT...

Think about this... NOBODY that uses organic oil ever does these test and thus will never know if there is premature rig/piston/head wear, etc...

As a mechanical engineer, my opinion is that it's really just a CYA manuever by AMSOIL to avoid lawsuits and make them some extra $$.

I'd feel more comfortable running AMSOIL for 25K without tests than organic oil for 3.5K without test...
Then you clearly don't know enough about oil. :p

You don't need to run oil analysis while running dino oil &amp; changing at 3,500 miles. That's silly. All modern conventional oils are capable of going 3,000 miles, some much longer, particularly the diesel oils.

Oil analysis is the ONLY way you can determine if your oil is still functioning satisfactory. You have to remember that any and all oils are worthless if they have solid particles in it. It doesen't matter if it's AMSOil, Havoline or GodOil.

No full flow spin on oil filter removes ALL particles from the engine oil. Some, infact, are absolutely horrible at it. Further, they do not remove water. They cannot give back a depleated TBN. When they become saturated, they no longer filter, which is even harder on the oil, depleting its additive package even more.

Again, there is much more to oil longevity than the oil itself, and there is NO WAY to tell without oil analysis... unless things are so bad that you can tell the oil has physically degraded, which would be about worst case scenario....

You do realize that, depending on the grade, AMSOil isn't the best..... right?

The 25,000 mile oil change is marketing, just like the 3,000 mile oil change is marketing.
Originally posted by: Hammer

i think i'll stick with what BMW says since that seems to be working so far.
BMW cares that their cars last until after the warranty period, nothing more. Same with all manufacturers. Do you really think they have your best interest in mind when they write the service manual?

I challenge you to spend 20$ and have your oil analyzed after 12,000 miles. I will give you the oil analysis fee via PayPal if it shows that your oil is still 100% viable.

I wouldn't be surprised if you get an emergency call stating impending engine failure, LOL(yes, they do that.. since important things like aircraft engines are a primary user of oil analysis - and for good reason).

But again, depending on which synthetic you use, if you use a good oil filter.. and most important of all, your driving habbits and environment, I estimate that it will show your oil should've been changed anywhere from 2,000 to 5,000 miles before.

If you're lucky, it will show that it needs to be changed now, but hasn't been severely depleted.
 

Caveman

Platinum Member
Nov 18, 1999
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Eli... Obviously, there is a marketing elemet in any product, including oil.

The bottom line is this: ENGINE problems are what is diagnosed in an OIL analysis. You don't have oil problems when your engine is running nominally.

Folks using organic oils never run oil analysis.

Again, It's not that I think an oil analysis is a bad idea...

It's that if you use the oil analysis argument for synthetic at a givern interval, then you must apply the same reasoning to organic oils.

You should still run an analysis on organic oil every 12k if you think you should run a synthetic analysis at 12k.

Again, if it were me, I'd feel more comfortable running AMSOIL for 25K intervals with no analysis than conventional for 25K (changed at 3.5K intervals) with no analysis.

Changing the oil "more often" doesn't "magically" get rid of engine problems that can occur in both organic and synthetically lubricated engines.