i have an acura cl 3.0, and the manual says that only to change oil filter with every other oil change. they recommend changing the oil at 7.5k so changing the oil filter at 15k or the second oil change. i notice that when i start up my car after an oil filter change, my oil pressure light takes 2-3 second to go away. i doubt that oil filter get clog up so soon. so what do you guys thing about honda's recommendation?
do you change your oil filter with every oil change?
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Patman
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It's a crazy recommendation, as you'll leave behind more dirty oil when change time comes around.
This is the Bobistheoilguy board, not "pennypinchers anonymous"... Why leave a quart of dirty oil in the engine to save $2?. Fill the filter as much as possible before you put it on (halfway if it mounts sideways) and it will eliminate much or all of the lag in the light. Or maybe some oil is held up in the block by the check valve...No-stop me before I go there again! Good luck, RW
Pretty crazy idea if you ask me.
But thats what GM recommended in the late 80's and early 90's.
Sounds 100% outawhack...change new oil, leave crusty filter....naw....are you sure something didn't get lost in the kanji? I can understand the opposite being an Amsoil abuser....don't follow that advice and I'll sleep better.
They probably say make those reccomendations so they can claim that their cars are more effecient than other cars and don't need maintenance as often. I would change the filter with every oil change
Ryan's probably right, they are going for low cost of ownership ratings.
Oil filters efficiency of trapping smaller particles improves with age (up to a point) so maybe they factor that in also.
Oil filters efficiency of trapping smaller particles improves with age (up to a point) so maybe they factor that in also.
People say that but I've never seen data to support it.
I used to work at a beverage plant and new filters always worked better than old ones. This company spent over $1 million/yr on filters so we collected data and nothing ever suggested old filters worked better than new ones.
What were you filtering out of the water at the beverage plant? What type of filter was used? How did you know when it needed changing. How did you determine the improved efficiency?
Actually recommendations are based on what the competition is recommending. Engine makers are only concerned with the engine lasting as long as the competition. If they recommended 3,000 miles changes the engine would last longer but people would buy the car that can go 7,500 miles between changes. It all has to do with marketing. They learn what to recommend based on what the customer wants. It has nothing to do with what is best for the engine. It's the same with submicronic bypass filters. Some filter makers claim with their filters you can go farther between changes. It's B.S. the better the filter and smaller the filter the more often it needs to be changed.
A filter that doesn't clean oil can go a long time between changes. If I see a filter with long life written on it I laugh. The only reason I change a full flow filter is I have seen them break down. Paper doesn't have an unlimited life even on the shelf.
I'm considering using a spin on filter with a stainless steel mesh element. I could probably install it and forget it. The Motor Grard 0.01 micron filter wouldn't let it get dirty. I ordinarily change the pleated paper filter every 2 years. The Motor Guard protects the full flow from acid and water. After 2 years the pleats are still strong and clean. The same goes for recommending oil that is too thin to protect the engine well. It helps them with their corporate average fuel economy and they figure the engine will last long enough.
Ralph
A filter that doesn't clean oil can go a long time between changes. If I see a filter with long life written on it I laugh. The only reason I change a full flow filter is I have seen them break down. Paper doesn't have an unlimited life even on the shelf.
I'm considering using a spin on filter with a stainless steel mesh element. I could probably install it and forget it. The Motor Grard 0.01 micron filter wouldn't let it get dirty. I ordinarily change the pleated paper filter every 2 years. The Motor Guard protects the full flow from acid and water. After 2 years the pleats are still strong and clean. The same goes for recommending oil that is too thin to protect the engine well. It helps them with their corporate average fuel economy and they figure the engine will last long enough.
Ralph
I'm sure I've read this in several different places. Air filters have the same characteristic of starting out at a lower efficiency on filtration and improving with age. The only problem is they also start restricting the flow of air/oil at some point and that becomes a bigger issue than filtering the small particles.
The application you described may have started out at the efficiency that was desired, and couldn't tolerate lower flow. It's hard to compare becuase the filtration requirements for that process are likely quite different than in Automotive.
Maybe someone has a link that explains it, if I find one I will post it.
I agree completely. It's easy to see happening. One company makes a car do 100,000 mile tuneups by adding platinum plugs and pretty soon they all are doing it. How long were these plugs available before they became standard equip? They want as much profit as they can get and adding expensive plugs or oil and filters cuts into those profits.
[/qb][/QUOTE]I agree completely. It's easy to see happening. One company makes a car do 100,000 mile tuneups by adding platinum plugs and pretty soon they all are doing it. How long were these plugs available before they became standard equip? They want as much profit as they can get and adding expensive plugs or oil and filters cuts into those profits.[/QB][/QUOTE]
Very true we are not dealing with a bunch of idiots. These people know where the profits are. If you own a fish market you don't teach people how to catch fish. Clean oil doesn't generate profits.
Ralph
Very true we are not dealing with a bunch of idiots. These people know where the profits are. If you own a fish market you don't teach people how to catch fish. Clean oil doesn't generate profits.
Ralph
I think it is a dangerous recommendation. Filters vary. Oils vary.
I've taken apart filters with 900 sq. cm. of surface area and others with 2800 sq. cm. All of which were supposed to be "equivalent" PH-8A filters.
I also have a study that was done in 98 with 3 CH-4 oils. At 400 hours of testing one increased the oil pressure differential at at the filter 10 psi, another increase 20 psi, and the third 69 psi.
Put the first oil with the better filter and you have no problem with pressure and by-pass. (still some dirty oil). But put the 3rd oil with the cheaper filter and I believe you have problems.
I've taken apart filters with 900 sq. cm. of surface area and others with 2800 sq. cm. All of which were supposed to be "equivalent" PH-8A filters.
I also have a study that was done in 98 with 3 CH-4 oils. At 400 hours of testing one increased the oil pressure differential at at the filter 10 psi, another increase 20 psi, and the third 69 psi.
Put the first oil with the better filter and you have no problem with pressure and by-pass. (still some dirty oil). But put the 3rd oil with the cheaper filter and I believe you have problems.
We did filter water, but for the most it wasn't water that we were filtering.
We used cartridge membrane filters rated for 1 mircon absolute. Pressure drop across the filter was monitored to determine when the filter needed changing (or cleaning). 8psi was the cutoff point. Efficiency was determined by plating and counting yeast colonies. The problem with the dirty filters was when you started getting higher pressure drops, you can force dirt through the media.
The filter media is not the same as a automobile filter so maybe you can't compare it.
Another problem with dirty filters is flow surges cause dirt to get through. For more information see dynamic filter efficiency under interesting articles.
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