knapp9

iTrader: (1)

I don't mean to start another mindless debate on oil filters, or argue which is the best brand. But I haven't found much at all about this topic when I searched. I am curious on opinons regarding the importance of a top by-pass valve on an oil filter versus one located on the bottom of the filter.

As I understand it, the value of a top by-pass valve is that it substantially lessens the possibility of oil flowing back over the dirty side of the filter in the event the filter actually goes into by-pass mode, and then reintroducing that dirt to the engine again. I for one could never tell if a filter runs in by-pass mode. But IF it ever did, flushing matter big enough for the filter media to catch in the 1st place back into the engine strikes me as a big bad boy, and a fairly important consideration in selecting filters. Especially the longer a filter is in use.

My question is, is it even worth worrying about? Especially when you consider that most filters (as best I can determine) have that valve located on the bottom of the filter, not the top...including Nissan oem, Mobil, Bosch, Purolator, K&N, SuperTech, Fram, and STP (I think). Brands I've found with the top by-pass are few: Motorcraft, Wix, and NAPA Gold. I simply don't know about the rest, like Amsoil, Hastings, AC Delco, & Baldwin.

To me, as one prioritizes filter features, this one ranks right up there with good anti-drain back valves and may be more important that media efficiency. But it also thins down the field of contenders considerably.

Does it depend on application (normal vs extended drain)? Am I making this more important than it needs to be? If not, why are there so few filters with the top by-pass design?

Obviously , Chuck.

VQ35DE

Mobil 1 , M1-105 is the best top valve made that fits our cars.

Colonel

Which motor do you have as the filters vary slightly based on being a 30 or 35.

VQ35DE

Mobil 1 M1-110,108,106,104 and the top valve M1-105 fit the 3.0 and the 3.5 which I have.

Colonel

Have you used the 105? Is there any fitment issue? And how does the size match up to the 110 or 108? Oil has been beat to death but the filter is where most of my interest is. Comment freely.

nick778

The Bosch uses the top bypass valve and I like it for this reason plus it uses a semisynthetic media for good flow and filtering. I use the Nissan OEM and Bosch.

VQ35DE

The M1-110 is longer than the 108 & 106, the 104 is no longer than 110 but larger diameter, and 105 is same length as 104 but even larger diameter than 104.

Colonel

Very interesting...looks like I will have about 5 filters on the floor in a couple days. Have you used the 105 yet? In your other thread you mention a NAPA filter...?

knapp9

iTrader: (1)

I've used the Mobil 110 and the Bosch 3323. The by pass valve on them sure looked like it was on the bottom of the filter to me, not the top. I'll have to give the 105 a look see next time I'm in the store to inspect the valve location. The Wix 51356 clearly has a top valve, and seems to fit the "oem sized 20 micron optimum" category.

knapp9

iTrader: (1)

I've used the Mobil 110 and the Bosch 3323. The by pass valve on both sure looked like it was on the bottom of the filter to me, not the top. I'll have to give the 105 a look see next time to see where the valve is located. The Wix 51356 fits the VQ30, and clearly has a top valve. It seems to fit the "oem sized 20 micron optimum" category. No NAPA store is close to me, but I know Wix makes the gold line for them.

I guess I'm just curious on the need for and perceived value of a top located by-pass valve.