Does bypass location really matter?

[Stelth]

My Ford calls for the FL820S, a very nice filter which features thread-end bypass and silicone ADBV. But I was looking at some of the higher priced filters such as Wix, Bosch, and Mobil 1, and they all have dome-end bypass valves.

Ford likes the thread-end bypass, but does it really make much difference?

 

[greystone]

I don't have an answer for you but have had the same question.

 

[WMSmotorhead]

Wix filters usually have the bypass at the thread end. It doesn't matter much.. Wix says that "If your filter is so full it bypasses, do you want it to pump oil across the dirty media before it goes into the engine?"......

The Ford filter you speak of is very close to a Purolator Pure One.

Truth is, your oil filter shouldn't be left on the car so long that it clogs and starts bypassing.

Most of the premium filters.. Wix, Purolator, Hastings/Baldwin should fit the bill of the vehicle just fine. There's lots of good filters. Any of those family of filters, amongst others should be a reliable quality alternative.

 

[steve20]

Good Luck trying to claim any oil related engine repairs on your Ford warranty if you have used an aftermarket (dome bypass) filter

 

[hhu168]

Originally Posted By: steve20
Good Luck trying to claim any oil related engine repairs on your Ford warranty if you have used an aftermarket (dome bypass) filter


What's the chance of your claiming an oil related engine repair under warranty anyway?

 

[Sayjac]

Been discussed here over time. Yes, Ford/Motorcraft seems to prefer thread end and seems somewhat particular about it in some applications. But, even all Motorcraft filters are not thread end bypass, some are dome end.

The idea of thread end being that, the silt doesn't wash off the media when the filter is bypass.

That said, based on my reading here including the late Gary Allan (rip), it's just not that big a deal either way. And in some applications with pics posted here, thread end does seem to take up some space that dome end has for media.

 

[goodtimes]

Mopar Chrysler filters I use have thread end just like MC, are also made by Purolator. Other cars I service in family use dome end. There is no way except by logic to base an opinion, nothing feels different. If the oil is thicker, engine colder, air colder, revs higher, the bypass valve opens more without the filter being clogged. There is something logical to the claim of washing the element of it's dirt more in those situations with dome end. Cars with bypass in the block are even better, much better, I would say.

 

[Sayjac]

It seems something similar holds true for Mopar filters as Motorcraft. While the Purolator made Mopar has thread end bypass, as this thread shows an alternative Mopar filter for similar applications has dome end bypass. Apparently Mopar doesn't think bypass position makes a big difference.

You can also note the comments regarding more media area with the dome end bypass.

 

[dickwells]

It is wise to always use Motorcraft on 4.6 family engines. The passages at the end of the head to the camshafts are quite small and any restriction there will cause cam failure.

 

[RF Overlord]

Originally Posted By: sayjac
including the late Gary Allan (rip)
What?! Please tell me I'm reading that wrong...

*EDIT* I did some searching and found the thread. I am saddened by his passing. The man sent me a DVD of an oil filter factory video at his own expense, just because I expressed an interest. A true gentleman.

 

[WMSmotorhead]

Originally Posted By: steve20
Good Luck trying to claim any oil related engine repairs on your Ford warranty if you have used an aftermarket (dome bypass) filter


Umm... Any good oil filter that is approved will have the notice that all Vehicle warranties apply when using X Filter. the filter in question meets the manufacturer's specs.

 

[Bruce T]

Below is the old thread that I remember Gary Allan participating in. Sigh, this topic reminds me of him.

Teach Me About Dome vs. Thread:

https://bobistheoilguy.com/forums/posts/1725652/

 

[river_rat]

Shoot I didn't know we lost Gary. He was the best. I am so out of the loop as usual. His passing saddens me a lot.

But I don't want to steer this thread off topic.
A lot of OEM filters from reputable manufacturers use dome end bypass, and that ought to say something. I prefer thread end, all things being equal, because my filter sits dome end down where any debris that didn't get stuck to the media will settle. If the filter sat horizontally, I woudn't care.
But even with dome end down, I don't think it makes much difference--as when the bypass begins to open (as it does regularly on my engine when cold or at RPM much over 3000 when hot) there is still oil flowing the correct direction through the media tending to hold dirt in place. Just some of the oil is going around the media per pass.

Just my theory.

(Anyway, look at the high mileage cars typically get nowadays with whatever oil and filter the quicky lube puts on...if the car isn't hot-rodded around all the time or neglected.)

 

[Stelth]

How long do you think I could run a Motorcraft FL-820S? I'm going to do a 5K (miles) OCI this time, but if I want to extend it a bit in the future, is the FL-820S up to the task?

 

[RF Overlord]

I used to run the FL400S in a Taurus for 10k intervals so I see no reason the FL820S shouldn't go the same. I would have a used oil analysis done after the first extended run just to be safe, though...

 

[Hallmark]

Originally Posted By: Stelth
How long do you think I could run a Motorcraft FL-820S? I'm going to do a 5K (miles) OCI this time, but if I want to extend it a bit in the future, is the FL-820S up to the task?


Since Ford recommends normal service OCIs of 7500 miles on engines in warranty with FL-820S/FL-500S filters, it appears that extending your OCIs wouldn't be an issue.