Why 3,000 miles

[Craven]

Why is 3000mi the magic number, because the oil change places and and filter companys like Fram say so, even if the car companys state a longer oil change cycle. Why, because they are selling the stuff.

 

Most people in the world don't change there own oil. So let's say you take your car to a oil change place every 3000mi. And you keep your car for 100,000 mi.

That's 33 oil changes. But if you change you oil by the book at 5,000 mi. That's 20 changes, so how much extra money did the oil change place make.

[MorganM]

I go by what the owners manual says. 3,000 miles is the 'old school' milage. Oil is a lot better now and so is the internal combustion engine.

 

For my KIA its 7,000 under 'normal operating conditions' and 5,000 for 'extreeme operating condtions'. Read in your manual what it defines those terms as; might supprise you. Here in MN about 8 months of the year are 'extreeme conditions'.

[Craven]

I go by what the owners manual says. 3,000 miles is the 'old school' milage. Oil is a lot better now and so is the internal combustion engine.

 

For my KIA its 7,000 under 'normal operating conditions' and 5,000 for 'extreeme operating condtions'. Read in your manual what it defines those terms as; might supprise you. Here in MN about 8 months of the year are 'extreeme conditions'.

I don't know what extreem condtions means to your Kia, but if you go to a oil change place they always say "we recomend you come back in 3,000 miles" and put that little sticker in your window to remind you.

[thealleyboy]

It's usually 3000K or 3 months.

 

I always assumed that it takes this long for moisture and contaminants to build up to an unacceptable level.

True that you could go longer (in terms of miles) with modern oils. Problem is, condensation will still be a problem in three months regardless of the quality of the oil.

 

good luck, John

[spanky_pete]

My cars that run dino oil get changed every 3k, or as soon after as I can get around it to. It's what I was taught to do growing up and I've stuck with it for that reason more than any other.

 

However, my WRXs are running synthetic so they get changed every 7,500mi.

[mudduck]

I change the oil when I feel it needs to be changed. When the oil starts to look dark on ythe dipstick, is ussually when it gots changed.

 

My toyota truck it got changed about every 1000 mi because it didn't get driven a whole lot, and when it did, it was usually off road

 

My subaru git an oil change about every 2000- 3000miles

[Craven]

It's usually 3000K or 3 months.

 

I always assumed that it takes this long for moisture and contaminants to build up to an unacceptable level.

 

True that you could go longer (in terms of miles) with modern oils. Problem is, condensation will still be a problem in three months regardless of the quality of the oil.

 

good luck, John

Not if you get the oil up to operating temp. and drive it. If you drive 3mi to work and back and never get the oil up to operating temperature and yes condensation would be a problem. As far as contaminants, if you use a good high Quality oil and air filter and keep the oil clean, there is no need to change the oil that often.

[MorganM]

I don't know what extreem condtions means to your Kia, but if you go to a oil change place they always say "we recomend you come back in 3,000 miles" and put that little sticker in your window to remind you.

 

Note what I said; read the owners manual. Dont buy what some shmuck at Jiffy Lube gets paid to tell you.

[Craven]

Note what I said; read the owners manual. Dont buy what some shmuck at Jiffy Lube gets paid to tell you.

I guess what I was asking. What dose Kia call extreem?

[MorganM]

I guess what I was asking. What dose Kia call extreem?

 

Might be different per manufacturer but normal winter conditions in MN are 'extreem conditions'. Driving on a dirt road often is considerd 'extreem'. Constant stop and go traffic is again, extreem conditions. I think also driving in hot weather often was considerd extreem also. Oh and consistant high speed / rpms also considerd extreem.

 

Same type of classification justification was in my friends Toyota 4Runner onwers manual also. I was supprised they considerd these conditions extreem when frankly its daily driving for a lot of us.

[Craven]

Might be different per manufacturer but normal winter conditions in MN are 'extreem conditions'. Driving on a dirt road often is considerd 'extreem'. Constant stop and go traffic is again, extreem conditions. I think also driving in hot weather often was considerd extreem also. Oh and consistant high speed / rpms also considerd extreem.

 

Same type of classification justification was in my friends Toyota 4Runner onwers manual also. I was supprised they considerd these conditions extreem when frankly its daily driving for a lot of us.

Sounds like they want you to change your oil at 5,000 miles to me. My 86 Ford diesel says 5,000 normal and 3,000 extreem, Which they say is towing or dusty conditons.

[MorganM]

Also its not JUST about contamination. Oil does break down in tough conditions; reguardless of contaimination. I'm not saying that justifies a 3k oil change sheduel but its another factor to consider that I have yet to see mentioned.

[85Sub4WD]

Almost all of my driving is "extreme" ie city stop - and - go, and the recommended oil change interval in my owner's manual for "extreme" conditions is 3,000 miles. I also look at the dipstick and feel the oil - if it feels different than it does new out of the bottle, oil change time.

 

Funny how it gets to that point every 3,000 miles

 

Also its not JUST about contamination. Oil does break down in tough conditions; reguardless of contaimination. I'm not saying that justifies a 3k oil change sheduel but its another factor to consider that I have yet to see mentioned.

 

that's my main concern about prolonged use of oil, because the broken-down oil can leave deposits - and yes ALL oil breaks down, including synthetics - they just take longer

[mtsmiths]

Why is 3000mi the magic number,

 

In the immortal words of Tevya, "Fiddler on the Roof" --

 

TRADITION!

[Craven]

Also its not JUST about contamination. Oil does break down in tough conditions; reguardless of contaimination. I'm not saying that justifies a 3k oil change sheduel but its another factor to consider that I have yet to see mentioned.

Oil dose not break down!!! Oil gets contaminated if you keep it clean it will last a life time. There is a diesel Tugboat running around the Great Lakes I forget her name, that has the same engine oil in it since it was put into sevice 1953. The filtering system they use cleans the oil down to less than 1/10th of a micron. All they do is add additives that are recomended after testing.

[roxtar]

my new toyota with the 2zz-ge engine is 5000 miles. revs to 8200 before hitting the fuel cutoff. 180 n/a horsepower out of 1.8 liters

[idosubaru]

from what i've read, the actual pertroleum may not break down but the products they use in combination with the oil to create different weight ranges and properties do break down. oils with larger weight ranges say 10w-40 require more of these products than 10w-30 to create that wider range. therefore it is best to stick to oils with less weight range because it is actually more oil and less other stuff. i'm sure the differences are very minute, so it's really not important and i'm not by any means saying 10w30 is better than 10w40.

 

if you're coming up with a one-size-fits-all approach (which none of us would believe that 3,000 miles is a necessity because at 3,500 the motor doesn't blow up), then you're going to debate all day because it isn't meant to be a perfect fit for everyone and everbody. some of it is attributable to advertising and marketing. a quantitative way to change oil is to have it chemically analyzed and tested every 1,000 miles or so and once it reaches some predetermined saturation level (again, some number someone had to come up with) then it's time to change. do this testing through a couple oil changes and average it out to 2,345 or 4,562 or 7,432 or whatever your oil change requirement is for your vehicle, geography, driving style..etc. but who wants to do all that?

[Craven]

from what i've read, the actual pertroleum may not break down but the products they use in combination with the oil to create different weight ranges and properties do break down. oils with larger weight ranges say 10w-40 require more of these products than 10w-30 to create that wider range. therefore it is best to stick to oils with less weight range because it is actually more oil and less other stuff. i'm sure the differences are very minute, so it's really not important and i'm not by any means saying 10w30 is better than 10w40.

 

if you're coming up with a one-size-fits-all approach (which none of us would believe that 3,000 miles is a necessity because at 3,500 the motor doesn't blow up), then you're going to debate all day because it isn't meant to be a perfect fit for everyone and everbody. some of it is attributable to advertising and marketing. a quantitative way to change oil is to have it chemically analyzed and tested every 1,000 miles or so and once it reaches some predetermined saturation level (again, some number someone had to come up with) then it's time to change. do this testing through a couple oil changes and average it out to 2,345 or 4,562 or 7,432 or whatever your oil change requirement is for your vehicle, geography, driving style..etc. but who wants to do all that?

I agree

Here is something from Mobil

 

Mobil

Technical Bulletin

Mobil Oil Australia Limited

Automotive No. 863

 

WHY DO WE CHANGE OIL?

Some machinery, for example steam turbines in power stations, does not require oil changes, the original charge being usually expected to last for the life of the machine, which may be 20 years or more.

 

Why then does the oil in a motor car engine have to be changed at regular intervals, which may represent only about 50 hours running?

 

To answer this question, it is as well to state that except under very unusual circumstances, oil does not “wear out”, “break down” or otherwise deteriorate to such an extent that it needs to be replaced. What happens is that it becomes contaminated with water, acids, burnt and un-burnt fuel, carbon particles and sludge so that it can no longer provide the desired degree of protection for engine components. But, it will be argued, most modern vehicles have an oil filter. Why does this not remove the contaminants? The answer here is that a filter can only remove solid particles above a certain size. It cannot remove water, acids, or fuel dilution, all of which pass through the full-flow filter just as readily as the oil.

 

As we have already seen, the oil contains additives to combat the effects of these contaminates. But there is a limit to the amount of contamination that even the best oil can neutralize, and there comes a time when the only satisfactory procedure is to drain the oil and replenish the engine with a new charge. Thus there arises the necessity for regular oil changes.

 

The question should now be asked “How often should engine oil be changed?” Unfortunately there is no simple answer to this. From what we have already discussed, it will now be apparent that we change oil, not because it has deteriorated, but because it has become contaminated with various harmful substances, and the greater the rate at which these enter the oil, the sooner an oil change will be necessary.

 

The things that influence this include engine condition and method of operation. A vehicle that is used mainly for short distance stop-start running will require more frequent oil changes than one used for regular long distance traveling, and a worn engine with leaky piston rings will contaminate the oil quicker than a new engine in good mechanical condition. Thus it is not unusual to specify oil change periods in terms of numbers of miles or days, whichever comes first.

 

It should also be borne in mind that a high performance product like Mobil 1 can handle more contaminate than other products, and hence longer oil change periods can be justified.

 

As a final comment on this subject, it is worth mentioning that it is normal for oil to darken in service. This is not an indication that the oil has deteriorated. It shows that it is picking up its load of contaminates and keeping then in suspension, where they can do no harm, and where they can be removed from the engine when the oil is changed.

[MorganM]

Okay so I was half wrong... oil DOES "break down" but that is BECUASE there is contamination.

 

The number of miles is irrelivant; its the circumstances the oil is placed in that dictates how long it does its job properly. Mobile even acknowledges that even their oil, with all its fancy addatives, has its limitations and does eventually 'break down'.

 

Circumstances are different between that tug boat, my subaru, your subaru and frankly between any other engine. Stiffy Lube tells you 3k so they make more $, car manufacturers tell you whatever to cover their butts, and people belive what they want.

[Craven]

Okay so I was half wrong... oil DOES "break down" but that is BECUASE there is contamination.

 

The number of miles is irrelivant; its the circumstances the oil is placed in that dictates how long it does its job properly. Mobile even acknowledges that even their oil, with all its fancy addatives, has its limitations and does eventually 'break down'.

 

Circumstances are different between that tug boat, my subaru, your subaru and frankly between any other engine. Stiffy Lube tells you 3k so they make more $, car manufacturers tell you whatever to cover their butts, and people belive what they want.

 

That about somes it up.

[Gravityman]

My buddy had a suzuki sidekick and his manual said every 7000 miles. If you use the old non synthetic oils you may have to change it at about 3000 miles if you drive it hard. If you driving your car hard then run full synthetic mobile 1, I swair by it!. I ran it in my old jeep and I would put 9000 miles between oil changes. That engine ran very good I wish i put it in my transmission before it craped out on me 3 times! The only thing you really need to do is change out your filter. Full synthetic oil does not break down like non synthetic do, Hence SYNTHETIC, they didnt make this crap just to sell more expensive oil. It was produced for Formula 1 racing before released to the public and now every one that races professionally uses it. Turboed engines use it for a reason, My 05 Legacy 2.5GT Demands it. The only way I would change synthetic oil any sooner is if it was ran through a turbocharger to prevent coking. ENJOY!

[thealleyboy]

There are all kinds of theories and opinions on this topic, as evidenced above.

I base my comments on what a professional fleet manager taught me about maintenance. I'm talking about someone who's livelihood depended on making the "right" decisions in managing several thousand cars over the course of his career.

His educated opinion was that virtually all vehicles fall under "extreme" driving condititions - as defined by the manufacturer. This is especially important when a car is still under warranty. It is nearly impossible for a manufacturer to sucessfully challenge a claim for a vehicle that follows the severe duty schedule. Therefore, the 3000/3 rule applied for all vehicles in his fleet.

The comment about condensation "burning off" through normal driving is not correct. (take a sample of used oil to a lab if you don't believe me). The only way to rid your system of h20 contaminated oil is to drain it.

Oil does "break down", but changing at 3000k almost guarentees that it will not deteriorate to the point of causing wear.

John

[Seahag1978]

Well, there must be something to changing oil every 3,000 miles. When I bought my Honda new, the dealer gave me a certificate from Pennzoil that guaranteed my engine for LIFE as long as I could prove with receipts that the oil was changed and replaced with Pennzoil every 3,000 miles... that's a pretty gutsy guarantee.

 

My Hyundais and Baja owner's manuals both recommend 7,500 miles... that's way too long in my book. Just my opinion... that and a buck and a half will get you a quart of oil

[Syonyk]

Cost of oil for more frequent changes: X.

 

Cost of an engine rebuild: In most cases significantly greater than X.

 

Really, frequent oil changes are cheap, especially if you do it yourself. You're not going to hurt anything by changing the oil more frequently, but you can accelerate engine wear/damage by not changing it often enough.

 

Also, I prefer to change my oil more often, because I don't know what sort of maintenance previous owners have given the car. My RX-7 regularly spit out black oil until the engine blew. After rebuilding it (and cleaning it up), it spits out still mostly amber oil. I'd rather change oil more frequently to clean old crap out.

 

-=Russ=-

[thealleyboy]

My RX-7 regularly spit out black oil until the engine blew. After rebuilding it (and cleaning it up), it spits out still mostly amber oil.

-=Russ=-

Dark-colored oil isn't necessary something to freak over.

It is normal for motor oil with the detergent additives to get dirty - especially in a neglected motor. It will start to clear up, but it may take half a dozen changes to get amber. This tells you that the oil is doing it's job in gently cleaning out your engine.

John