Wix oil filter design philosophy

[Navi]

The Wix website is an interesting read.

https://www.wixfilters.com/en-us/support/training/wix-performance.html

Basically.their standard Wix oil filter is designed around balancing out their 3 measures of oil filter greatness. The Wix XP filter is designed for extended drain intervals but its not the best according to their design philosophy.

I use the standard Wix filter because the price is right and its better than what came with the car. If you are one of those guys who wants the best oil filter that would be the Purolator Boss.

Im not sure what extra benefit would be with the worlds greatest oil filter whether that be Purolator Boss or Fram Endurance. Maybe if I was doing track racing, daily.towing or extreme off road I would use those to be on the safe side.

We have a 2015 Toyota RAV4.where the oil has been changed according to the maintenance light meaning 7 to 10k miles. Whatever the dealer or local mechanic had in stock was used for the changes which means I have no idea what they put on. Here we are 10 years and 150k miles later and it still runs good.

At the end of the day I think most people are best served with the standard Wix filter. Better than what came with the car...less than 5 dollars on Rockauto.

 

[ZeeOSix]

An oil filter can have high efficiency and high capacity, while still have a pretty low pressure drop (ie, dP vs flow curve). The OG Fram Ultra and Titanium are good examples of that. Of course it takes media like used in those filters, being dual layer wire-backed full synthetic depth filtering media. When using a standard blend media, it's still possible to obtain something close to the OG Ultra level, and increasing the media total area goes a long way to get better capacity and lower pressure drop. The old yellow Purolator PureOne was very efficient and has a low dP vs flow curve, and it was just a cellulous/sythetic blend media. But it has a lot of media area back then. One thing I've notice over the years is that manufacurers keep cutting back on the media are. One example are Motorcraft filters, specifically the FL500S which I've cut open after use and measured the media are. Along the line, it was decreased from 227 sq-in to 120 sq-in ... almost a 50% reduction. Probably a cost cutting measure, but something I didn't like to see.

 

[ZeeOSix]

This is what we see with the Purolator Boss and Wix XP type of filters - ie, low efficiency but relatively high capacity. They are also inefficient because they release (slough off) a lot of the already captured debris due to increased dP as they load up. Ascent's ISO 4548-12 efficiency test showed how bad the Boss and Wix were in this respect.

But as mentioned above, there are ways to have high capacity and still maintain a high efficiency even as the filter loads up. Filters with high ISO 4548-12 efficiency have to by definition be able to hold already captured debris very well. They can't be that high in efficiency without being able to hold captured debris very well as the filter loads up and the dP increases.