extended OCI's but what wait a sec.

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I've heard a lot about extended (over 3K miles)OCI's with synthetics, but what about the oil filter and the oil just getting "dirty"? I know this might sound like a newbie question, but even if an oil can withstand the abuse of an engine, it still gets dirty with contamination right? Correct me if I am wrong, but this is kinda why I stick with changes at 3K miles. Am I missing something? I just feel like removing all of the contamintation is the way to go.
 
yes and no. I don't feel contamination is bad enough at 3000 miles to warrant a change. 5000 maybe, but still unlikely. it depends on how, where and in what weather you drive.

on GF-4 oil, under severe conditions, the norm is 5,000 miles for many many engines.
 
Synthetic oils can resist breaking down longer than conventional oil...but conventional can go more than 3k under a variety of circumstances. I was always of the opinion that 6k was about the maximum length a filter could go before the bypass valve would open. But I guess it depends on how well it filters and how large the area of the filter media is.

There is nothing wrong with sticking to 3k intervals. Heck I do 3k intervals with Mobil 1 synthetic on one of my vehicles. But apparently, the average oil filter can go longer depending on a number of factors.

Some of the OEM's are raising their recommended intervals to 6k plus!!! And they do not say change the filter in between. But again, I am partial in agreement with you and am leary that a filter will not clog up pretty quick under the right driving conditions.

A K&N filter will get you some nice dirty oil for example :) My best recommendation if you plan to switch to synthetic oil to increase to a longer interval than 4k miles, would be to use a quality brand paper air filter, and an oil filter designed for extended useage such as a Mobil 1 brand filter.
 
A mechanically sound engine will put little if anything into the oil. The extended OCI is largely about additives being used up, and especially the TBN getting to low. Check the used oil analysis on here and see that 10-15k miles is not to difficult. Some better oils can go even lomger(I invite you to define your term here). The filter will catch the not oil soluable/solids. You are correct in that things soluable in the oil can/will only be removed with a change. I believe your definition of extended OCI is to low 5-6k is reasonable with any rated/name brand dino let alone a syn which would I think be over at least 10k.
 
These extended OCI's are all about the gov't, EPA, & the environmental nuts anyway. They want you to use less oil so they upped the OCI's on newer cars.

Heck, they even started sealing some of the transmissions now too where you cant service them yourself!

I say 3k on dino is fine...I go 3k on syn on my HM vehicle, and 4k on syn-blend on my lower mileage vehicle. I am considering switching the HM vehicle to dino every 3k instead of syn now that I know that the only real benefit of syn oil is an extended OCI (for me anyway).

On my lower mileage vehicle, I MIGHT start pushing the blend to 5k as long as I do not use any oil in between. If you have low miles and plan to change less than 5k, no need for syn unless you live where it is extreme cold alot or you can just afford the extra money for piece of mind.
 
As was said, it depends on the service. 3k may be warranted if service goes in either direction. If it's short trips ..the moisture and excessive dwell time in fuel enrichment will warrant the change out ..while if it's something like delivery or taxi like service, the mismatch in fuel use, as indicated by mileage, warrants the change out.

Engines are a lot cleaner now. The longer that you're out of the warm up cycle, the longer the oil can stay in service. It's the same with filters, but they can stretch out further than oil can if the service allows. The loading factors just aren't there enough to saturate them.
 
what's funny is my 95 accord's manual recommends 7500 miles under "normal" or non-severe conditions. i have 311K miles and have always tried to change at 3k but i put so many miles on that at 3k, i almost have to get a change once per month. So i am considering a synthetic with maybe 6K. I am in Texas so I would consider the conditions to be severe.
 
If GM's OLM is accurate (and all indications seem to confirm it) ..and other vehicles static recommendations parallel GM's NON OLM equipped engines, then there are very few that fall into severe service except those who engage in limited or short trip usage. Some DO fall into the 3k type decay rate ..some at or near the factory recommended (otherwise) 7500 ..but many go beyond ..way beyond. I think the record (by my memory) here is 13k ..and that's conventional.

So ..I mostly think "severe" is used too severely ..or casually (depending on how one views it
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Originally Posted By: joel95ex
what's funny is my 95 accord's manual recommends 7500 miles under "normal" or non-severe conditions. i have 311K miles and have always tried to change at 3k but i put so many miles on that at 3k, i almost have to get a change once per month. So i am considering a synthetic with maybe 6K. I am in Texas so I would consider the conditions to be severe.


extremely conservative strategy.

You can go at least 7500 miles on say M1. If I drove that much, I'd be doing 10,000 miles on M1.

You can go further (one year or 20,000 miles plus) using AMSOIL.

Just cause its hot doesn't mean severe conditions. dusty maybe, but heat in itself outside of the car isn't that bad, not nearly as bad as cold.


regular service in my camry dictates 10,000 mile oil changes on synthetic blend! and we would have a similar climate to texas i believe.
 
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Interesting about the filter comments. That said, does anybody have any comments on the durability of WIX filters?
 
Contamination is really not a concern as that large volume of oil can hold alot of stuff. As stated earlier it is the depletion of the additives that are the big factor. As long as the oil does not become so used up as to allow sludge and excessive varnish deposits the air and oil filter take care of most contamination issues. (Except excessive fuel or coolant contamination)

I would not really call going over 3,000 miles as an extended OCI. With modern engines I would say going over 5-6,000 miles would be considered extending the OCI.

The oil filter would have no problem going double/triple the 3,000 mile OCI. Many say the filter works better over time.
 
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Either 3000 0r 5000 or 7500 or??? In all these cases the engine will outlive the rest of the car, especially the transmission. You are truly wasting yor money if you stay with the current OCI even more so if you go with synthetic and stay at 3-4000.

If you like changing your oil then there is no cure for you, 3000 is your psychological limit
 
I do yearly OCI's on my Mazda using Amsoil, and their filter. I only drive about 5k miles a year, and have no problem going that amount of time between changes.
 
I do 6K Miles using Amsoil and their EAO filter. I have recently sent a used oil analysis to Terry Dyson who said I could safely double the OCI and Filter Interval to 12K Miles.
 
Originally Posted By: StevieC
I do 6K Miles using Amsoil and their EAO filter. I have recently sent a used oil analysis to Terry Dyson who said I could safely double the OCI and Filter Interval to 12K Miles.


Nothing like getting confirmation that you're doing the right thing. My last used oil analysis was great and at 5k miles the tbn on my fill of Pennzoil Platinum 5w30 was 6. So it could have easily gone 7.5 - 10k miles. I've settled on 6k miles for peace of mind.
 
OP asked about filters. A good quality filter (wix, purolator, amsoil, etc) can last a very long time. The Honda Crv manual suggests changing the oil filter every other oil change, with oil change intervals of 10k miles under normal conditions. So 10k miles for a filter would allow me to sleep fine at night :)
 
Originally Posted By: Spector
If you like changing your oil then there is no cure for you, 3000 is your psychological limit


Spector: Now there is a nice turn of words, kudos! "The 3000 mile psychological limit." I love it!!
 
Originally Posted By: webfors
Originally Posted By: StevieC
I do 6K Miles using Amsoil and their EAO filter. I have recently sent a used oil analysis to Terry Dyson who said I could safely double the OCI and Filter Interval to 12K Miles.


Nothing like getting confirmation that you're doing the right thing. My last used oil analysis was great and at 5k miles the tbn on my fill of Pennzoil Platinum 5w30 was 6. So it could have easily gone 7.5 - 10k miles. I've settled on 6k miles for peace of mind.


He said I might even be able to triple both except the Silcon and Insolubles were getting high and could be due to an air filter not doing a great job.

My TBN after a 6K run was 6.3 on ASL 5w30.
 
Originally Posted By: joel95ex
I've heard a lot about extended (over 3K miles)OCI's with synthetics, but what about the oil filter and the oil just getting "dirty"? I know this might sound like a newbie question, but even if an oil can withstand the abuse of an engine, it still gets dirty with contamination right? Correct me if I am wrong, but this is kinda why I stick with changes at 3K miles. Am I missing something? I just feel like removing all of the contamintation is the way to go.

Most of the time, the oil is worn out before the filter gets dirty. So, you change the oil. It makes sense to change the filter while you're under there, because it's cheap and easy while you're under there. That's why oil and filter changes usually go together.

Sometimes the filter gets dirty before the oil does. So, you change the filter. You could change the oil as well if you want, but that's up to you; a sump of oil is a lot more expensive than a filter. That's why some people who run REALLY long oil change intervals (10k miles and up) like to change their filters halfway through.


3,000 miles is really short. I can't imagine your oil filter getting clogged in that interval unless your engine is really dirty on the inside and/or your air filter is letting too much dirt in.

As said above, modern engines don't even produce gunk for the filter to catch unless they're busted somehow. Even older engines won't be bad if they're running well.
 
Five thousand miles in NOT an extended OCI in normal driving conditions. A 5000 OCI is the new 3000. Oils and engines are a lot better than they were even 15 years ago. If you don't believe that, then some people here might as well change their oil every 500 miles (the original OCI during the time of the Model-T)...
 
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