The Mann OEM Audi filter question

[Georgi1]

I have always used the original Mann filter on my 2.8 V6 Audi and over the years it got updates. The anti drain back valve was rubber and then it is white silicon, the filter media itself was that dark brown/orange and is now very bright yellow - most likely blend media. However the design remain the same.
What is very strange for me is the ONLY 4 RATHER SMALL HOLES for oil to pass. There are another 10 different brand oil filters for my engine and none of them has such a small number and size of holes. In Germany for example the second most used best filter after OEM/Mann would be Mahle. Even their filter has double the number holes.

This is an example with the cross ref filter from Purolator. Although smaller it has double the overall holes. Even this small tiny Toyota filter has more overall holes than it.

Any thought on that?

 

[ZeeOSix]

The pressure drop across that base plate with 4 holes must still be acceptable for the engineer(s) who designed it. They just don't make a design like that without verifying the flow performance. Most people can't get a good estimate of how something like that flows oil just by looking at it ... it needs to be ran through a flow analysis.

Besides, engines use a positive displacement oil pump for a reason, to ensure it forces oil adequately through various components that have different flow resistance. The engine's oiling system is typically has 12-15 times more flow resistance than an oil filter.

 

[shortyb]

Odd if another German filter (ie; Mahle, Hengst) would be different in the same application. The design parameters are very specific among auto manufacturers and finding something as "insignificant" as an oil filter that is drastically different across suppliers would be rather unusual. For example, my 2.0T CCTA engine uses a metal can spin-on with a plastic standoff for "upside down" mounting and all of the OE "German" ones available (VAG, Mann, Mahle, Hengst) are identical except for part numbers and labeling.

 

[Chris142]

For example, my 2.0T CCTA engine uses a metal can spin-on with a plastic standoff for "upside down" mounting and all of the OE "German" ones available (VAG, Mann, Mahle, Hengst) are identical except for part numbers and labeling.

And if you use ANY other brand it will dump oil all down the front of the engine when removed.

 

[shortyb]

And if you use ANY other brand it will dump oil all down the front of the engine when removed.

Always amazed that it doesn't dribble even a drop when spun off. Yet another reason to use the OE speced "German" ones (my last Mann was made in Spain though).

 

[ZeeOSix]

Always amazed that it doesn't dribble even a drop when spun off. Yet another reason to use the OE speced "German" ones (my last Mann was made in Spain though).

Does that filter have an ADBV? If not, then the oil is draining out so there isn't anything to dribble when the filter is removed.

 

[shortyb]

Does that filter have an ADBV? If not, then the oil is draining out so there isn't anything to dribble when the filter is removed.

Yep. White silicone one. 5-hole base plate too.

 

[ZeeOSix]

Yep. White silicone one. 5-hole base plate too.

Then it probably isn't sealing very well if other oil filters with an ADBV will retain oil that comes out when the oil filter is removed. Or the oil might be draining out the center tube if the media is pretty porous.

 

[shortyb]

Then it probably isn't sealing very well if other oil filters with an ADBV will retain oil that comes out when the oil filter is removed. Or the oil might be draining out the center tube if the media is pretty porous.

Oh there is still oil in it when taken off. Just nothing comes out when you do. Likely what oil that would, has already drained from the center tube back into the engine after shutdown.

 

[Chris142]

Always amazed that it doesn't dribble even a drop when spun off. Yet another reason to use the OE speced "German" ones (my last Mann was made in Spain though).

I get ones with fram, stp etc and they make a mess

 

[skyactiv]

Once had a GTI and my wife had an A4 that used an oil filter with a stud on it. I've had a Fram and even a Mann filter leave the stud and plastic thing in the block a few times. Switched to Mahle and it never happened again.

 

[Georgi1]

Odd if another German filter (ie; Mahle, Hengst) would be different in the same application. The design parameters are very specific among auto manufacturers and finding something as "insignificant" as an oil filter that is drastically different across suppliers would be rather unusual. For example, my 2.0T CCTA engine uses a metal can spin-on with a plastic standoff for "upside down" mounting and all of the OE "German" ones available (VAG, Mann, Mahle, Hengst) are identical except for part numbers and labeling.

Yes, Hengst and Mahle are different. I have pictures of them too. There must be a reason for the only 4 small holes and I am still not sure why no other manufacturer would do the same way for whatever reason it was done

I have had Tiguan with CCTA and I cut open 17 or so filters and here is the clip and topic

That Fram stud on the picture above can happen to all brands. It is not hard removing it on the Fram and few others because they have that nasty hex cut off where you can use a wrench, while the well made Mann and the other rebrands you need a big pipe wrench

 

[ZeeOSix]

There must be a reason for the only 4 small holes and I am still not sure why no other manufacturer would do the same way for whatever reason it was done

Could be to keep the base plate ridged instead of making it thicker with more holes that wouldn't drop the dP across the base plate much to justify more holes. Even there are only 4 holes, they aren't that tiny in flow area.

 

[ZeeOSix]

This is how base plate holes can be misleading with respect to looking at them and trying to estimate how they flow oil.

This was the base plate on a Fram Ultra XG3600. It had 8 small holes, each only 0.20 inch in diameter. Total combined flow area of the 8 holes was only 0.251 in^2. Hot oil at 15 cSt is close to what 20W-50 would be at 100C (212F).

Even at a flow of 10 GPM through the base plate, the dP across the base plate was only 1.6 PSI. Even with the oil much thicker at 500 cSt, the dP was 3.0 PSI. A base plate with more or larger holes might drop the dP to 1.0 PSI with hot oil at 10 GPM. It really gets you nothing significant.

 

[shortyb]

Yes, Hengst and Mahle are different. I have pictures of them too. There must be a reason for the only 4 small holes and I am still not sure why no other manufacturer would do the same way for whatever reason it was done

I have had Tiguan with CCTA and I cut open 17 or so filters and here is the clip and topic

That Fram stud on the picture above can happen to all brands. It is not hard removing it on the Fram and few others because they have that nasty hex cut off where you can use a wrench, while the well made Mann and the other rebrands you need a big pipe wrench

Wow, super comprehensive video. I watched the entire thing. Surprisingly seems several of the 'Merican filter brands are actually re-labeled German-made (probably Mann) filters. Takes a lot of the guesswork out of making a very specification intense filter. Probably saves a lot in the manufacturing cost to have them sourced like that too. With Mann+Hummel's recent acquisition of WIX and Purolator, and coming under their manufacturing umbrella, it's much less surprising that this is done for those filters. I'm sure whatever spin-off brands that were sourced from Wix and Purolator are now MH too.

Still don't understand the Mahle and Hengst differences with this filter type as you say. I have used both on occasion over the past few years that were externally identical (except labeling and part #s) to the Mann ones I usually use. Right down to the 5 hole base plate and white ADBV. Didn't cut any open, so don't know about internal differences. All came from FCP Euro and recent Mann ones have the ScanTrust QR verification code on the box so all appeared genuine. No matter though, they all worked and performed fine and thats what counts.

 

[Georgi1]

Could be to keep the base plate ridged instead of making it thicker with more holes that wouldn't drop the dP across the base plate much to justify more holes. Even there are only 4 holes, they aren't that tiny in flow area.

I get what you are saying and thanks for the great info. I also think as you say "4 holes must still be acceptable for the engineer(s) who designed it."
I also think that way. The 2,8L 12valve was introduced in 1991 and at that point in time Audi were making very reliable engines compared to later ones. Most of the early 90s engines outlives the modern day AudiVw engines 2:1. But My point is there must be a reason for that 4 holes & the size they are. My concern is actually why other filter makers NOT doing the original design? And when I say other I mean everyone else. This OEM Mann is the only one that is made like that. That engine got update in 1995 model year (mine is 1997) which included 1 extra valve in the block for not draining oil and also that 930/21 filter was introduced and replaced the previous ( Mann W719/30)
taller but smaller filter and it was also used for VW Passats and Audi A6 with the later 30valve 2.8 V6 and even was factory equipment of the Audi S4 B5 with the somewhat high performance TWIN turbo. So it must be good enough to supply those 2 snails.. (these engines were money pits and not long lasting)
Another interesting thing is the Mann filter tube inside has just regular placement of the passage holes, unlike the Purolator which has them oriented in like a whirlpool spiraling down which I have only heard is to improve flow but yet different than OEM design

On the info of the filter it says
Bypass Valve Opening Pressure = 4.3511 psi; Anti-drain back valve = 1, Thread Size (G) = 3/4-16 UNF

And here are few different german manufacturers that at some point of time were/are OEM suppliers for various different engines and they chose to probably just keep the "universal" stamping plate. I have had them before and those holes are more and larger so the logic where they are bigger number but smaller diameter does not apply. They may be doing it for their own cost savings with universal base plate but what do I care if it doesn't do any good for the engine with the "extra potential" flow and possibly them being the bottle neck backwards
1. Bosch
2.Hengst
3. Mahle

 

[ZeeOSix]

Another interesting thing is the Mann filter tube inside has just regular placement of the passage holes, unlike the Purolator which has them oriented in like a whirlpool spiraling down which I have only heard is to improve flow but yet different than OEM design
View attachment 341847

The center tubes that look like a "spiral" aren't like that to improve flow ... it's simply due to the way the center tube is manufactured, and the spiral design is supposedly to give it more rigidity.

On the info of the filter it says
Bypass Valve Opening Pressure = 4.3511 psi; Anti-drain back valve = 1, Thread Size (G) = 3/4-16 UNF

Wow, that's a low bypass valve setting. Maybe one reason there is only 4 holes in that filter is because it was originally designed for an engine with a pretty low output oil pump. The low bypass setting seems to point that way too.

And here are few different german manufacturers that at some point of time were/are OEM suppliers for various different engines and they chose to probably just keep the "universal" stamping plate. I have had them before and those holes are more and larger so the logic where they are bigger number but smaller diameter does not apply. They may be doing it for their own cost savings with universal base plate but what do I care if it doesn't do any good for the engine with the "extra potential" flow and possibly them being the bottle neck backwards
1. Bosch
2.Hengst
3. Mahle
View attachment 341823View attachment 341824View attachment 341825

A lot of aftermarket filter makers design oil filters that will fit and work on many different engines, so could explain why they use a different base plate design with more holes or larger holes. The only time any oil filter can "improve flow" is if it can keep the oil pump out of pressure relief a bit more at high engine RPM and high pump flow. Like said earlier, if 10 oil filters all had a dP vs flow different between them of a few PSI, it's not going to matter to the oil pump or an adequate flow of oil to the engine. There's really nothing to worry about in terms of flow on the filter with the 4 holes - if it was an issue they wouldn't be making it like that.

Can you try to measure the hole size and post it here? Bet the total area isn't much different than the example I gave earlier of the Fram Ultra with the eight 0.2 in diameter holes, which have only a few PSI of dP with high flow. Like said, dP vs flow is very deceptive by looking at something like a base plate ... the dP vs flow needs to be calculated to get a good grasp on it.

 

[CleanSump]

The baseplates aren't specific to a particular engine. The baseplates are standardized on a particular size of filter by the manufacturer. Hence, two filters from the same Asian OEM with the paint scheme and labeling of the Asian OEM can have different baseplates if made by different companies in different countries under contract to say Honda or Subaru. Just an example, Mahle makes very good filters for German cars and wouldn't starve your VW/Audi engine.
Of course, one is free to use a different brand if one wishes.

 

[ZeeOSix]

Looking at this photo it looks like the combined area of the 4 holes would be at least the same area as the flow hole in the threaded filter mount, which is smaller than the area of the center hole in the base plate. Nothing to worry about.

 

[rollins.]

The fewer # of inlet holes has been a Mann-Hummel thing for decades (fuel and hydraulic filters included).Non-issue.
https://s7g10.scene7.com/is/image/mannhummel/W_950.13-1?qlt=82&ts=1779403543639&dpr=off
comp. to Fleetguard LF3331 for example
........
https://s7g10.scene7.com/is/image/m...er-with-box-1?qlt=82&ts=1774293853457&dpr=off
https://s7g10.scene7.com/is/image/mannhummel/W_719.4-1?qlt=82&ts=1779403675930&dpr=off
https://m.media-amazon.com/images/I/81SLlLILdtL._AC_SL1500_.jpg

The by-pass opening pressure of the filter is 43.511 PSI :
https://www.mann-filter.com/us-en/c...t.html/w930/21_mann-filter.html#technicalData

M

Thread 'Bypass Valve pressure specs (Mann for VW/Audi)'

Apr 11, 2006

Does anybody know the bypass pressure valve specs for these two filters?

- VW/Audi 078-115-561-J (Mann 930/21) for Audi 1.8T

- VW/Audi 068-115-561-B (Mann 940/25) for Audi V6


For some reason the smaller 930/21 costs almost double of the larger 940/21. I don't know if the 940/25 is a LongLife filter.

• moribundman
• Replies: 23
• Forum: Engine Oil Filters