Assuming top quality oil and top quality filter, with a 5000 mile OCI, I'd change the filter at 1 year or 10k miles, whichever is first. YMMV. For high miles or particularly hard driving (dusty, towing, etc.), I'd change the filter at the OCI.
In the past, going thru the effort of ramps and crawling under, I'd generally change the filter. Now, with the MityVac and topside changes, I'm inclined to get maximum use from the filter, some of which are about $10 each and I don't like throwing money away unnecessarily (hey, that'll buy me lunch).
Another angle, let's say you were inclined to spend the $10 unnecessarily. I think draining the oil, refilling with inexpensive conventional, running it for 10 minutes, and the draining it all again would be a better "use" of a waste of $10 than throwing out a good filter. That short OCI would get more of the entire capacity of used oil out, than throwing out a perfectly good oil filter does. As a % I think you'd get almost all of the old oil out doing this, and at a buck a quart, it would likely be cheaper.
Exploring this further, let's assume your engine holds 5 quarts total with $10 filter. Let's assume the block will retain 1/2 qt, and the filter 1/2 quart. So a drain will extract 80%. Removing the filter 90%. Remaining amount is 10% that you cannot get out, dirty oil that will remain.
Instead, however, of removing the filter, you drain 80%. Refill and dilute with $5 of inexpensive conventional, now representing a 4 to 1 ratio. Run it to circulate, and then drain it all out again. On this 2nd drain you'd actually be extracting 4% of the old fluid. And it would cost less in this scenario, assuming you can get oil for less than the cost of the filter, and leave you with 96% fresh oil on the next fill, versus only 90% by just draining and removing the filter... Food for thought. YMMV.
My OCIs are now all based on time, not miles. I'm changing them far before I reach XXX miles, and sadly often dumping oil with as little as 1000 miles on it. I'm comfortable leaving a quality filter on it for a year or 18 months, since sometimes the filter barely has 2000 or so miles on it in that time frame, especially if it's a PITA to get to (skip plates, etc.). Consider a good filter is designed to last a year AND a lot of miles, something at 2000 miles and 12-18 months is fine.
The amount of oil left in the filter is probably 1/4 to 1/2 quart so it's not a huge amount and if there's low miles it's not particularly dirty.
In the past, going thru the effort of ramps and crawling under, I'd generally change the filter. Now, with the MityVac and topside changes, I'm inclined to get maximum use from the filter, some of which are about $10 each and I don't like throwing money away unnecessarily (hey, that'll buy me lunch).
Another angle, let's say you were inclined to spend the $10 unnecessarily. I think draining the oil, refilling with inexpensive conventional, running it for 10 minutes, and the draining it all again would be a better "use" of a waste of $10 than throwing out a good filter. That short OCI would get more of the entire capacity of used oil out, than throwing out a perfectly good oil filter does. As a % I think you'd get almost all of the old oil out doing this, and at a buck a quart, it would likely be cheaper.
Exploring this further, let's assume your engine holds 5 quarts total with $10 filter. Let's assume the block will retain 1/2 qt, and the filter 1/2 quart. So a drain will extract 80%. Removing the filter 90%. Remaining amount is 10% that you cannot get out, dirty oil that will remain.
Instead, however, of removing the filter, you drain 80%. Refill and dilute with $5 of inexpensive conventional, now representing a 4 to 1 ratio. Run it to circulate, and then drain it all out again. On this 2nd drain you'd actually be extracting 4% of the old fluid. And it would cost less in this scenario, assuming you can get oil for less than the cost of the filter, and leave you with 96% fresh oil on the next fill, versus only 90% by just draining and removing the filter... Food for thought. YMMV.
My OCIs are now all based on time, not miles. I'm changing them far before I reach XXX miles, and sadly often dumping oil with as little as 1000 miles on it. I'm comfortable leaving a quality filter on it for a year or 18 months, since sometimes the filter barely has 2000 or so miles on it in that time frame, especially if it's a PITA to get to (skip plates, etc.). Consider a good filter is designed to last a year AND a lot of miles, something at 2000 miles and 12-18 months is fine.
The amount of oil left in the filter is probably 1/4 to 1/2 quart so it's not a huge amount and if there's low miles it's not particularly dirty.
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