Say I go with an Amsoil filter Eao80 that's good for 25,000 miles... Would you guys say it's a good idea to change the oil every 7k miles or so and leave the same oil filter on? I could do an oil analysis but it would be the same cost as just changing the oil so I figure I might as well. That way I get a fresh sump too.
Change oil but not filter?
- Thread starter wcbcruzer
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That is what I am doing on 3 engines. I change the oil every 5-7 thousand miles and leave the Eao on. It has been said by a good source, that the Eao gets better with miles. I am just starting the 15K (4th oil change with the same filter on.)
With your Cummins engine, I would run the filter for two oil cycles....or 15K on the filter and about 7.5K on each oil change.
With your Cummins engine, I would run the filter for two oil cycles....or 15K on the filter and about 7.5K on each oil change.
Originally Posted By: wcbcruzer
Say I go with an Amsoil filter Eao80 that's good for 25,000 miles... Would you guys say it's a good idea to change the oil every 7k miles or so and leave the same oil filter on? I could do an oil analysis but it would be the same cost as just changing the oil so I figure I might as well. That way I get a fresh sump too.
I can't answer your question directly, because I always change oil and filter at the same time. In most cases, the filter is cheaper than the oil, so folks ask about changing the filter but not the oil. You want to do the opposite, which makes me wonder whether an expensive filter really makes sense?? And you don't want to pay for a UOA, so again I wonder what you expect to gain from an expensive filter?
Say I go with an Amsoil filter Eao80 that's good for 25,000 miles... Would you guys say it's a good idea to change the oil every 7k miles or so and leave the same oil filter on? I could do an oil analysis but it would be the same cost as just changing the oil so I figure I might as well. That way I get a fresh sump too.
I can't answer your question directly, because I always change oil and filter at the same time. In most cases, the filter is cheaper than the oil, so folks ask about changing the filter but not the oil. You want to do the opposite, which makes me wonder whether an expensive filter really makes sense?? And you don't want to pay for a UOA, so again I wonder what you expect to gain from an expensive filter?
A nicer filter will catch more debris over 20,000 miles than four cheap filters will over 5,000 miles each.
ACdelco filter section talk a great deal about having full unrestricted flow oil filter through the OCI other than just catching debris.
Is there any supporting data regarding the flow in an EaO filter after 10000 to 15000 miles.
Is there any supporting data regarding the flow in an EaO filter after 10000 to 15000 miles.
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EaO series are full synthetic media....does ac delco make a full synthetic media offering in any of their filters? If so, they are not common. By it's nature of design, a synthetic media filter will do a better job over a longer interval. A general mileage is not accurate, there are too many variables involved with one engine to the next, and likewise with different owners. You could have two exact same vehicles and two owners, and have totally different results using a top quality filter with one needing to be changed out much sooner due to operating conditions. Each has to find out for themselves if a piece of equipment works and for how long.
Ok guys, so I bought an Amsoil bypass filter to replace the Frantz I have now. I like the Frantz but my priorities have changed. Now my goal is to minimize oil changes so I can save time and resources. I will do an oil analysis and post the results here. I think I will leave the full flow filter on for 20k miles. I will also leave the bypass filter on for up to 50k miles or when the return hose no longer gets warm to the touch (if that ever happens). I'm actually going to be using a Donaldson Endurance oil filter as the full flow filter, which is the same exact filter as the Amsoil Eao80 I believe. The filter impressed me. It's supposed to be 98.7% efficient at 15 microns and 50% efficient at 7 microns! That's close to bypass filter status out of a full flow! That plus it's supposed to flow better than regular filters due to it's full synthetic media.
How about changing the filters every 5-7K and changing the oil at 20K?
THis thread leads me to the question: When you change the oil but not the filter, do you remove the filter and drain the oil, or not? I know of people who have done it both ways but have never pondered the pros and cons myself. What say you who do?
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Well Jim, I am from the old school. If I remove a filter, it stays removed.
Originally Posted By: Johnny
Well Jim, I am from the old school. If I remove a filter, it stays removed.
We musta gone to the same school. I'm not sure you could trust a filter seal the second time around. My thoughts would be the risk is not outweighed by an extra quart or two of dirty oil.
But, I was looking for opinions besides my own, so...
Well Jim, I am from the old school. If I remove a filter, it stays removed.
We musta gone to the same school. I'm not sure you could trust a filter seal the second time around. My thoughts would be the risk is not outweighed by an extra quart or two of dirty oil.
But, I was looking for opinions besides my own, so...
I'm old school too. BITOG has gotten me to change on a few things, but I can't change oil, and leave on old filter. I'm tempted to try it, but I would want the old oil out of the filter. The problem with draining the filter is the possibility of it leaking after re-use. The problem with not draining it is leaving up to 20% of old dirty oil to contaminate the new oil. I'll stick to changing the oil and the filter. Maybe BITOG can get me to change my ways a little more, but for now it doesn't look like that's going to happen.
I'm pondering an improvement of my filtering efficiency but those high efficiency filters are pricey, so in order to maintain my status as a tightwad, I gotta run 'em out longer to justify the expense. I'm less scared of leaving a little bit of "dirty" oil in when the filtering efficiency has been improved a lot. Still crunching some numbers on this but the thread got me to thinking....
I hear ya. I'd be comfortable using them if there would be absolutely no problems draining them and using them again. From what I understand that's hit or miss, and is what stops me. That and the OCD I have of leaving it on and having the additional dirty oil the filter is holding mixing in with new expensive synthetic oil. I realize there is residual oil in an engine that won't drain out, it's that plus the additional oil in the filter that bothers the helllllll out of me. Old habits die hard. Maybe someday I can convince myself, and change my ways.
FWIW Nissan's TD42 and TD42T indirect injected engines still used in many markets stipulate oil changes every 5,000km and filter changes every 10,000km.
Some years use two full flow filters, others use a full flow and a combination filter (incorporates a full flow and bypass element in the one body) so there are two filters on the engine and both use ADBV's
Some years use two full flow filters, others use a full flow and a combination filter (incorporates a full flow and bypass element in the one body) so there are two filters on the engine and both use ADBV's
It would be a great idea, I'd buy it.
I leave the EAO on the TL for at least 3 4-5,000 mile OCIs.
I shortened the OCI just slightly due to the extra dirty oil left in the filter.
My main reasoning in doing this is the filter is good for a minimum of 25,000 miles. Every time I take it off, it's not just the oil that's in the filter but the column of oil above the filter that drains out. When I start the car after prefilling the filter, the oil light still takes about 2 seconds to go out instead of instantaneous any other time. I figure I leave about 10% of the dirty oil in the engine this way but I save myself 4 dry starts.
On top of that, there's the theory that filters get slightly more efficient with age.
I shortened the OCI just slightly due to the extra dirty oil left in the filter.
My main reasoning in doing this is the filter is good for a minimum of 25,000 miles. Every time I take it off, it's not just the oil that's in the filter but the column of oil above the filter that drains out. When I start the car after prefilling the filter, the oil light still takes about 2 seconds to go out instead of instantaneous any other time. I figure I leave about 10% of the dirty oil in the engine this way but I save myself 4 dry starts.
On top of that, there's the theory that filters get slightly more efficient with age.
If I change the filter but not the oil, I could care less about the oil that remains in it. Taking off the filter to drain it is also more work that I'm trying to avoid with the risk of damaging the filter seal. My crankcase capacity is 3 GALLONS. Two extra quarts of old filtered oil ain't going to do anything. Same goes for smaller engines as well since they have proportionally smaller oil filters. Also, like you mentioned, there's still some old oil left in the engine after you do a normal oil change anyway.
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