technical basis for multiple oil change filter use

[edwardh1]

wonder what technical data is used to recommend the filter change frequency?
for
- change every time, in owners manuals

-change every other time, in owners manuals example Honda, Nissan etc

- change every 3rd time (fram ultra filters that have the 15000 mile recommendation). there might be some small difference between using it 15000 miles with the same oil (does anyone ever go that long?)
and leaving it on 15000 miles and changing the oil every 5000 miles.

are there any published studies anywhere? you know data rather than opinion? wonder if the oil testing companies ask how many miles on the oil, and how many miles on the filter- that would tell if there is any degradation from "the 1/3 cup of "old" oil left in the filter.

seems there would be a big "less mess" benefit of using a 15000 mile filter for three 5000 mile oil changes

I moved from the 3000 mile to 5000 oil change, maybe I need to go further, but that change 3 to 5 saves a lot of oil - a different topic I guess

 

[cat843]

The most likely scenario is reusing the old filter for 2X OCI is fine, but it may be dependent upon how dirty the engine is.

I have seen a case were a clogged oil filter caused the oil pressure light to come on. The relief should have worked but apparently did not. Only the filter was changed and the issue went away. Verified by mechanical gauge. Filter in question was the older style Amsoil and Amsoil looked at it and said the filter was full of engine crud, but not defective.

Some filters hold more like a QT of oil vs 1/3 of a cup.

 

[Greasymechtech]

Technical basis... reducing filters at the local landfill

 

[Dave Hess]

I do 20K mile oil filter changes, but with 3 OCI's. Clean fresh oil = long engine life.

 

[OneEyeJack]

Current full flow oil filters are good for more than one oil change because they don't do much. They certainly don't get in the way of oil flow and if a filter ever gets to the point where the by-pass opens all the time instead of just opening on a very cold start then there's some real abuse going on.

 

[Nate1979]

Ask Honda.

 

[RoadRaceJosh]

I once saw a differential pressure gauge installed on the oil filter hydraulic tubing bender. I liked that idea a lot as it would show when the filter was "full" and replacement was required. Other good information could be inferred such as which filters hold more/filter out less and have greater restriction to flow.

 

[Y_K]

filter caking

 

[gathermewool]

Just a few things:

1. IMO, how long (in miles, hrs) is much more relevant than how many times a filter is used. You may change your oil every 3k miles, while I change mine every 6k. Same OFI...

2. Every car is different. My car was purchased used, but has a good maintenance history and has no mechanical issues that would lead me to believe that an extended OFI is inappropriate, whereas a shorter interval may be appropriate for your jalopy.

3. I would not say that new oil is degraded by what used oil remains, at least not in the sense most seem to mean, but that the used oil is diluted into the new oil.

When you change your oil, what you drain is not 100% depleted; some (maybe a lot) of additive remains. The new oil is not, for the intent of this argument, cleaning up the old oil, depleting the new oil.

Originally Posted By: Mr Nice
I do 20K mile oil filter changes, but with 3 OCI's. Clean fresh oil = long engine life.


Add one thing to achieve long engine life: top off, if necessary.

This is my third OFI for the Fram Ultra installed on the Civic in my signature, which will likely take me to 18-20k miles total for the filter.

I wonder if it will even be close to its capacity then.