I changed the oil in my sister's '02 Toyota Highlander v6 and installed a NAPA Gold filter. Same oil as before (Mobil 1 5w30), the only difference was switching from a Fram (orange) to a NAPA Gold filter and the engine is definitely running smoother. Is the NAPA filter flowing more oil? I'm certainly pleased with the results but curious to see if you think changing filter brands made the difference.
New filter = smoother?
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Probably not. A usably clean oil filter contributes only a tiny flow restriction. In some conditions the pressure regulation eliminates even that trivial difference.
The power of suggestion is vastly more influential.
The power of suggestion is vastly more influential.
What djb said; you're probably falling prey to the placebo effect. New oil is a little thicker, things are a little different, maybe it just seems smoother subjectively. Even if the filter elements itself limits flow, the bypass is always there to allow oil by if its too restricted.
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No, most engines run quieter the first 1000 miles of an oil change. I believe the fresh oil simply dampens better until it starts to shear out and pick up contaminants. But some engines seem to "like" certain oils better than others.
Once the engine is started and up to full oil pressure, the filter is virtually invisible in the system. Filters can definitely make a difference in start up, but running? No IMO.
I agree with others - if it's not a placebo effect, then the fresh oil is making a small difference in the sound.
I have noticed (like The_Jake wrote) that some oils let the valvetrain (in a hot engine) make more noise after about 1,000 miles in service whereas other oils last a full OCI without that noise. Such noise may not matter, but I'd rather not have it, so I avoid those oils in the particular engine. (I am comparing oils with the same SAE specifications, not any Euro spec oils.)
If an old filter had a failing ADBV, then a new filter could make a difference at startup, especially on engines with a timing chain. But the OP's engine is one of the MZ variants, with a timing belt.
I have noticed (like The_Jake wrote) that some oils let the valvetrain (in a hot engine) make more noise after about 1,000 miles in service whereas other oils last a full OCI without that noise. Such noise may not matter, but I'd rather not have it, so I avoid those oils in the particular engine. (I am comparing oils with the same SAE specifications, not any Euro spec oils.)
If an old filter had a failing ADBV, then a new filter could make a difference at startup, especially on engines with a timing chain. But the OP's engine is one of the MZ variants, with a timing belt.
Originally Posted By: KCJeep
Once the engine is started and up to full oil pressure, the filter is virtually invisible in the system. Filters can definitely make a difference in start up, but running? No IMO.
The filter is invisible in terms of flow at start-up also because of the positive displacement oil pump - unless the oil is so thick that the oil pump goes into pressure relief and shunts oil flow back to the sump. The oil would have to be super thick for that to happen at idle speeds after a cold start-up.
Only effect an oil filter would probably have on a cold start-up is if the ADBV let the filter drain out. And even then, most engines don't care if the filter drains out some because oil pressure is still achieved in 2~3 seconds, even with a drained oil filter.
Once the engine is started and up to full oil pressure, the filter is virtually invisible in the system. Filters can definitely make a difference in start up, but running? No IMO.
The filter is invisible in terms of flow at start-up also because of the positive displacement oil pump - unless the oil is so thick that the oil pump goes into pressure relief and shunts oil flow back to the sump. The oil would have to be super thick for that to happen at idle speeds after a cold start-up.
Only effect an oil filter would probably have on a cold start-up is if the ADBV let the filter drain out. And even then, most engines don't care if the filter drains out some because oil pressure is still achieved in 2~3 seconds, even with a drained oil filter.
Thanks guys, for all the replies. Not saying you are wrong about the results being psychological but the engine certainly feels smoother. Engine noise seems to be about the same as before so I'll wait to see how smooth the engine feels after this OC gets about 1000 miles on it. Hopefully it will be like it is now.
It's mind over matter.
New filter = smoother = are you related to ARCO?
Originally Posted By: RF Overlord
New filter = smoother = are you related to ARCO?
New filter = smoother = are you related to ARCO?
I believe I have noticed differences on cold starts. Between Napa Gols, Fram XG and K&N.
I doubt there was any placebo effect because what I WANTED to hear was that it would be pretty much as good with whichever brand's premium line I chose.
Three weeks ago I went with MaxLife 5W30 & XG7317 and start ups are not as good as they were with 5W30 & 1356 I used towards the end of last winter.
I had the same experience on my previous car between XG3614 vs. Napa 1348 (both with Syntec).
K&N might be better than both. In 2009 I had one in the summer along with my summer fill (GC + top-ups with 5W40) and due to low mileage I left it until late November. That winter I tried PP + 1348 and was disappointed with cold starts & warm ups - it was better with summer set up - I dumped it after 900Mi. I originally placed all the blame on the oil, but when the next year I tried stretch the thicker mix with a Napa filter, it didn't work like it did with the K&N.
I doubt there was any placebo effect because what I WANTED to hear was that it would be pretty much as good with whichever brand's premium line I chose.
Three weeks ago I went with MaxLife 5W30 & XG7317 and start ups are not as good as they were with 5W30 & 1356 I used towards the end of last winter.
I had the same experience on my previous car between XG3614 vs. Napa 1348 (both with Syntec).
K&N might be better than both. In 2009 I had one in the summer along with my summer fill (GC + top-ups with 5W40) and due to low mileage I left it until late November. That winter I tried PP + 1348 and was disappointed with cold starts & warm ups - it was better with summer set up - I dumped it after 900Mi. I originally placed all the blame on the oil, but when the next year I tried stretch the thicker mix with a Napa filter, it didn't work like it did with the K&N.
Well guys, the Highlander is now 2800 miles into this OCI and the engine is still running smoother than it did previously. Also, at this point the oil (same as before, Mobil 1 5w30) still looks as clean as it did when I put it in. At this mileage the oil used to be getting darker in color. Placebo effect: I would have to say no. I had no upfront expectations when I put in the NAPA Gold filter. I just thought I would try one because you guys seem to like them. In a week or two I will change the oil in my Focus. I will be using the same oil (Mobil 1 5W-20) and will install a NAPA Gold filter. Again, I have no upfront expectations but if I get similar results to my sister's car, I'll be a happy camper.
Hyde244 ... I have the same (year, model, engine etc.) car but with more miles on mine. What are you getting for gas mileage?
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