Relevance of changing the oil filter every OCI

Joined
Jan 3, 2020
Messages
867
Location
Brittany
When i got my car with 100k km, the inside of the engine was already clean like new thanks to being serviced at the dealer every 10,000 to 15,000 km with 5W40. In my 100k km of ownership i changed to oil approximately every 6,000 km with whatever was on sale, mainly synthetic or semi synthetic euro xW40.

I think it cleaned it even further since the filters now come out looking like new and they used to catch fine chunks of carbon. I felt it was stupid to change filters that didn't have anything in them and left them in the engine for 2 OCIs (roughly 12,000 km).

Now, even with a longer OCI of 10,000 to 13,000 km the filter is clean, not even brittle or anything and the oil still has a nice color. Maybe this has to do with my driving which is 60% highway, 40% country roads and no city driving at all, all on E85.

How would you feel about keeping the same filter for 2 OCIs for around 20,000 to 25,000 km? I know it's like putting your dirty socks back on after taking a shower, not that a filter costs much but it looks like it doesn't accomplish anything at all. I'm interested about your opinion.
 
Joined
Dec 28, 2011
Messages
4,517
When i got my car with 100k km, the inside of the engine was already clean like new thanks to being serviced at the dealer every 10,000 to 15,000 km with 5W40. In my 100k km of ownership i changed to oil approximately every 6,000 km with whatever was on sale, mainly synthetic or semi synthetic euro xW40.

I think it cleaned it even further since the filters now come out looking like new and they used to catch fine chunks of carbon. I felt it was stupid to change filters that didn't have anything in them and left them in the engine for 2 OCIs (roughly 12,000 km).

Now, even with a longer OCI of 10,000 to 13,000 km the filter is clean, not even brittle or anything and the oil still has a nice color. Maybe this has to do with my driving which is 60% highway, 40% country roads and no city driving at all, all on E85.

How would you feel about keeping the same filter for 2 OCIs for around 20,000 to 25,000 km? I know it's like putting your dirty socks back on after taking a shower, not that a filter costs much but it looks like it doesn't accomplish anything at all. I'm interested about your opinion.

What vehicle are we talking about? Engine? It can matter. If you feel your engine and filter are that clean, then look into a second OCI on the filter. Make sure the filter rating can handle the extended use first.

Can you elaborate on the brittle filter comment? Brittle is not a common comment concerning an oil-soaked filter. Were you expressing concern over tears in media?

As Demarpaint stated, leaving the can on for a second round does introduce about a 1/2 quart of old oil in the can. Something to consider.
 

OM605

Thread starter
Joined
Jan 3, 2020
Messages
867
Location
Brittany
The vehicle is my Mercedes C180. M111 engine, 4 cylinder 1.8L, port injection, DOHC, 16 valve, duplex timing chain, sump capacity of 5.5L.

A few times i saw the paper element becoming kind of brittle on cars with long overdue OCI. I'm talking years... and lots of sitting.
 

4WD

$50 site donor 2023
Joined
Sep 21, 2010
Messages
20,821
Location
Texas via IAH
I just did it on my Pentastar but not my underwear - no relationship at all - just “feelings”

That’s with a Fram XG rated for 20K - I’m doing two 5K rounds …
It still took the full 5 quarts to fill (top mounted cartridge) but my GM V8 holds back a quart with filter.
That’s in 8 quarts - and I can swap in a quart with my Fumoto anytime in 5 minutes …
 
Joined
Feb 27, 2009
Messages
8,089
Location
down in the park
When i got my car with 100k km, the inside of the engine was already clean like new thanks to being serviced at the dealer every 10,000 to 15,000 km with 5W40. In my 100k km of ownership i changed to oil approximately every 6,000 km with whatever was on sale, mainly synthetic or semi synthetic euro xW40.

I think it cleaned it even further since the filters now come out looking like new and they used to catch fine chunks of carbon. I felt it was stupid to change filters that didn't have anything in them and left them in the engine for 2 OCIs (roughly 12,000 km).

Now, even with a longer OCI of 10,000 to 13,000 km the filter is clean, not even brittle or anything and the oil still has a nice color. Maybe this has to do with my driving which is 60% highway, 40% country roads and no city driving at all, all on E85.

How would you feel about keeping the same filter for 2 OCIs for around 20,000 to 25,000 km? I know it's like putting your dirty socks back on after taking a shower, not that a filter costs much but it looks like it doesn't accomplish anything at all. I'm interested about your opinion.

I've left my diesel filter in for up to 50k, changing the oil (partly) every 10k. Diesel oil turns black of course but like with you the filter didn't appear loaded or catch anything that didn't get absorbed in the media.
 
  • Like
Reactions: Y_K
Joined
Jul 23, 2021
Messages
1,312
Location
PA
If the filter is designed for X number of miles or years, then leaving it on for 2 oil changes that total X (or stated X/2) is harmless and probably better than one OCI that totals the X. It does save a little money, it's less waste, and leaving it on removes a entire step and chance for leaking (double gasketing, etc.). If a filter can stand the same old oil for 10k, it can easily function on 2 oil changes at 5k each with a fresh amount of oil at the 1/2 way interval. I see no harm in it. And some benefit. $5 or 5 Euros saved even every year, may not seem like much but all savings add up in the aggregate to substantial amounts.

And note, you're never getting all the old oil out of the engine. About 10% +/- remains no matter what, so a 7 qt engine will have about 1/2 to 1 full qt remaining anyway. So the 1/2 qt or so in the oil filter is just a bit more dirty oil.

FYI, there's a few current threads on this topic.
 

4WD

$50 site donor 2023
Joined
Sep 21, 2010
Messages
20,821
Location
Texas via IAH
Some people use their filters for 2 OCI's, or more. Others like myself feel if the oil is being changed why leave up to a half a quart or more of dirty oil behind? Do what you feel is best. Topics like this can get heated real fast.........
Are you still using M1 ESP ?
Our AutoZone has the 0W30 for $32/jug… decent price for the good stuff 😷
 

4WD

$50 site donor 2023
Joined
Sep 21, 2010
Messages
20,821
Location
Texas via IAH
If the filter is designed for X number of miles or years, then leaving it on for 2 oil changes that total X (or stated X/2) is harmless and probably better than one OCI that totals the X. It does save a little money, it's less waste, and leaving it on removes a entire step and chance for leaking (double gasketing, etc.). If a filter can stand the same old oil for 10k, it can easily function on 2 oil changes at 5k each with a fresh amount of oil at the 1/2 way interval. I see no harm in it. And some benefit. $5 or 5 Euros saved even every year, may not seem like much but all savings add up in the aggregate to substantial amounts.

And note, you're never getting all the old oil out of the engine. About 10% +/- remains no matter what, so a 7 qt engine will have about 1/2 to 1 full qt remaining anyway. So the 1/2 qt or so in the oil filter is just a bit more dirty oil.

FYI, there's a few current threads on this topic.
And for me less cyclic stress on that infamous Mopar cooler …
 

OM605

Thread starter
Joined
Jan 3, 2020
Messages
867
Location
Brittany
I know that 20k km is the recommended service interval for other cars that share the same engine/filter as mine.
 
  • Like
Reactions: JC1
Joined
Jul 3, 2005
Messages
37,831
Location
NY
Are you still using M1 ESP ?
Our AutoZone has the 0W30 for $32/jug… decent price for the good stuff 😷
Yes I'm still using it. I grabbed six 5 quart jugs in December when AAP had a deal with a coupon code. I'll be set for a while, ESP imo is the perfect oil for all three of my vehicles.
 
Joined
Dec 10, 2010
Messages
1,479
Location
Lexington, NC
That is only 12000-15000 miles on a filter. Assuming you are using a good Mahle or Mann type filter, it should handle two OCI's very well. On other hand, I believe your car uses a cartridge that sits on top of the motor and is easily changed.
 

pbm

Joined
Apr 19, 2004
Messages
9,486
Location
New York
I usually change the oil filter every oil change but have done 2 OCI'S of 5k each on a Fram Ultra because Ford makes it a PITA to remove the belly shield on my cars. I used a Mityvac. I wouldn't do 2 OCI'S on an oil filter on a dirty (neglected) engine but otherwise I think it's fine using a high quality filter.
 

UncleDave

$50 Site Donor 2023
Joined
Jun 2, 2014
Messages
7,745
Location
Ca.
When i got my car with 100k km, the inside of the engine was already clean like new thanks to being serviced at the dealer every 10,000 to 15,000 km with 5W40. In my 100k km of ownership i changed to oil approximately every 6,000 km with whatever was on sale, mainly synthetic or semi synthetic euro xW40.

I think it cleaned it even further since the filters now come out looking like new and they used to catch fine chunks of carbon. I felt it was stupid to change filters that didn't have anything in them and left them in the engine for 2 OCIs (roughly 12,000 km).

Now, even with a longer OCI of 10,000 to 13,000 km the filter is clean, not even brittle or anything and the oil still has a nice color. Maybe this has to do with my driving which is 60% highway, 40% country roads and no city driving at all, all on E85.

How would you feel about keeping the same filter for 2 OCIs for around 20,000 to 25,000 km? I know it's like putting your dirty socks back on after taking a shower, not that a filter costs much but it looks like it doesn't accomplish anything at all. I'm interested about your opinion.

No problem - dont give it a single thought - why? Because it doesn't matter.

There is much more old oil left in the engine than in the filter. If old oil is such a worry why isnt anyone equally worried about that?

Changing underwear isnt much good if you just crap your pants right after you do it.
Which is what happens the second you start the engine with a new filter - the old oil runs right into the new filter.

A well constructed filter can easily go 20K miles on however many oil changes you want in between. Thats they they are called 20K filters.

Honda recommends and sets up their maintenance to change the filter every other OCI.

If anyone can show ANY difference in UOA's Ill happily change my practice - but no one can because there isnt any difference.

Im running an old style fram ultra for its third OCI now and Ill run them to 20K or hair over or under.


If it makes you feel better throw it away, but its simply assured waste.
 

hrv

Joined
Sep 14, 2021
Messages
1,280
No problem - dont give it a single thought - why?

There is much more old oil left in the engine than in the filter. If old oil is such a worry why isnt anyone equally worried about that?

Because it doesn't matter.

A well constructed filter can easily go 20K miles on however many oil changes you want in between. Thats they they are called 20K filters.

Honda recommends and sets up their maintenance to change the filter every other OCI.

If anyone can show ANY difference in UOA's Ill happily change my practice - but no one can because there isnt any difference.

Im running an old style fram ultra for its third OCI now and Ill run them to 20K or hair over or under.


If it makes you feel better throw it away, but its simply assured waste.
Really.... My 20201 Honda HRV Sport says Oil and Filter.... Thats in the owners book also...
 
Top