Filter Flow Rates - Premium Guard Site Observations

[KCJeep]

With all the changes and buy outs that have hit oil filter manufacturing the last couple of years, I started looking around and like many here became interested in the Premium Guard filters. I was looking at their site today and noticed a few things I found interesting.

First of all, Premium Guard actually posts "flow rates" for their filters on their site, most manufacturers don't. I've been looking at two sizes that fit my Mustang, the 241 series (Fram 3614 equivalents) and the 195 series (Fram 3600 equivalents).

For the standard paper cellulose media PG241, flow rate is listed at 15l (3.96 gallons) per minute. For the larger filter PG195 with the same paper cellulose media, the flow rate is listed at 20l (5.28 gallons) per minute. A significant difference in stated flow rate, and the only difference between the filters is the media area. However if you jump to the synthetic blend media extended use series, both the PG241EX and the PG195EX are listed to flow the same at 7.93 gallons per minute for both, which is significantly more than either of the paper cellulose filters of the same size.

The take away: According to Premium Guard there is a difference in flow affected by filter size for paper cellulose, but not their synthetic blend, and in spite of higher efficiency for the synthetic blend it flows better than paper cellulose does. (The standard filter is claimed to have 93% efficiency at 25 microns, the synthetic blend 99% at 25 microns.)

Common thinking here is a positive displacement oil pump will achieve what it needs to with any filter, and I've long subscribed to that myself, but these variations in the published flow rates by the manufacturer are thought provoking. Is it possible the paper cellulose or other poorly flowing filters end up going into bypass much more frequently since the pump is going to get the oil through anyway? Is flow actually "a thing" with oil filters after all?

I did not yet research other sizes for further comparison, that could be enlightening as well.

Link to the site:

Premium Guard Filters

 

[blufeb95]

What does the rate "flow-rate" even mean?

 

[ZeeOSix]

With all the changes and buy outs that have hit oil filter manufacturing the last couple of years, I started looking around and like many here became interested in the Premium Guard filters. I was looking at their site today and noticed a few things I found interesting.

First of all, Premium Guard actually posts "flow rates" for their filters on their site, most manufacturers don't. I've been looking at two sizes that fit my Mustang, the 241 series (Fram 3614 equivalents) and the 195 series (Fram 3600 equivalents).

For the standard paper cellulose media PG241, flow rate is listed at 15l (3.96 gallons) per minute. For the larger filter PG195 with the same paper cellulose media, the flow rate is listed at 20l (5.28 gallons) per minute. A significant difference in stated flow rate, and the only difference between the filters is the media area. However if you jump to the synthetic blend media extended use series, both the PG241EX and the PG195EX are listed to flow the same at 7.93 gallons per minute for both, which is significantly more than either of the paper cellulose filters of the same size.

Without also specifying the oil viscosity and dP at those flow rates, they don't really mean anything. You could try and contact them and ask them what those flow rates are based on - ie, what oil viscosity and dP.

Common thinking here is a positive displacement oil pump will achieve what it needs to with any filter, and I've long subscribed to that myself, but these variations in the published flow rates by the manufacturer are thought provoking. Is it possible the paper cellulose or other poorly flowing filters end up going into bypass much more frequently since the pump is going to get the oil through anyway? Is flow actually "a thing" with oil filters after all?

Yes, the PD oil pump will still force the same volume through the filter if it's a bit more restrictive than another filter. But as you mentioned, the more "flow restrictive" the filter is, the higher the dP will be across the media which could cause the bypass to open more unless the designer of the filter has set the bypass valve accordingly.

Flow "is a thing" with oil filters, only in the terms I just described. The filter's flow performance is described by the "Flow vs dP" curve, as shown in the example below. Ideally, the lower the curve (at a constant viscosity and flow rate), the better the filter "flows". But again, the PD pump will still supply the same oil volume to the filter and engine regardless of what filter is on the engine as long as the pump in not in pressure relief.

 

[KCJeep]

One takeaway is the smaller paper filters may be in bypass way more than you would think.

 

[ZeeOSix]

One takeaway is the smaller paper filters may be in bypass way more than you would think.

Yes, with all things kept constant except for the total media area, the dP will go up as the total media area goes down. That's one reason why smaller oil filters in the same model line can have worse efficiency, due to the higher dP across the media.

 

[OVERKILL]

I'd be a bit reluctant to take any claims from a company that doesn't actually manufacture the products they are selling at face value. They are reliant on the contract facility in Asia to produce a product that meets the claimed performance levels. How much oversight is there? How much random QC spot checking and ISO testing is being performed?

 

[KCJeep]

Good point, I’d presume that they are having them built to their specifications. With my limited experience regarding Asian manufacturing though, you have to watch them like a hawk because despite what you agree upon they will start cutting corners behind your back if you don’t pay attention.

That said the Premium Guards posted here have been consistently good. I bought my first Premium Guard built filter yesterday, a Carquest Premium, and the visual quality was evident.

 

[ZeeOSix]

That said the Premium Guards posted here have been consistently good. I bought my first Premium Guard built filter yesterday, a Carquest Premium, and the visual quality was evident.

How much are they going for?

 

[KCJeep]

I got it for $7.74 without even bothering with the easily available on line discount.

If I like this one as much as I think I will I may buy a larger quantity and use some online deals.