Originally Posted By: john_pifer
So, all filters don't have an ADBV?
I thought they all had one, but the question was, is it silicone or not?
Well, actually, some Frams actually come without ADBVs, for example the PH3675.
I went to see this other thread about it:
https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=3136522
From that thread I've taken a few quotes:
Originally Posted By: GSCJR
You were probably looking at PH9837 which is w/o adbv. PH3675 is w/adbv for that application.
Originally Posted By: David1
Originally Posted By: 440Magnum
Originally Posted By: Hokiefyd
Originally Posted By: NMBurb02
As far as I understand it, not all filters have ADBVs, as they are not needed in all applications. If the filter orientation in the Trailblazer is like my Burb's and the base of the filter faces up, there is no need for an ADBV because gravity does the job of keeping the oil from draining out of the filter.
An ADBV is still beneficial here, because oil above the filter in the engine oil galleries will push oil backwards through the filter due to head pressure. See below sketch. This shows what the oil will try to do after the engine is turned off and the system is no longer pressurized.
SO true, its hard to imagine why filters without ADBV's exist at all. All for the want of a few pennies, I guess...
Yea just to save a few pennies
also no bypass, thats crazy the one on the ENGINES have been known to FAIL...
heck they even show it on FRAM You tube page..
I'm heading to youtube... gonna see if I can't find what was talked about in the quote.