Who was it who mentioned Fram oil filters and dropping oil pressure? (2025 Update)

The early slant six (long filter) was PH8A. The short one was was PH43. BOTH have antidrainback valves according to their spec. Fram USED to make a PH8, which I believe was the same as the PH8A but without the antidrainback. Don't think it's been made since the 8A came out back in the early sixties. And I've had a lot of Slant 6 engines apart and cannot recall EVER seeing a backflow prevention device in the filter standpipe.

And just think about it for a moment. The oil comes in the OUTSIDE of the filter, through the ring of holes around the base. The drainback valve covers THOSE holes to keep oil from running back out of the filter. The standpipe goes in the CENTER of the filter, which is the OUT LET of the filter. How could a backflow prevention valve work in the standpipe? CAN'T - That's how. There is no backflow prevention valve on a slant six engine. PERIOD. It REQUIRES the backflow valve equipped oil filter to prevent the oil from draining out to the pan on every shut-down. If the backflow valve fails it takes several seconds of running to develop oil pressure - and on a cold day after a hot shut-down, it can be well over 10 seconds.

I've owned and driven the crap out of several slant sixes in my lifetime, and the rest of the family had quite a few more, which I serviced at least part of their lives.(except for my kid brother's , which he looked after because by then he was also a mechanic) Several of them went over 200,000 miles. All of them but one at one time or another had drainback / dry restart issues.

My last slant six was the '74 Dart Sport - and by that time I had given up on using fram filters. Cannot remember it ever having the "delayed oil light" problem except when the oil pressure switch leaked

- and then it would come on even on the road (when you came to an idle) as well as taking time to go off on startup.

The fram number is PH8A smallest to largest PH8-PH16-PH8A PH16 is also Wix 51085 IIRC

On that particular 5.4 the filter was remotely mounted behind the front bumper and horizontal. I never had the problem when changing oil, but then I never changed oil when the vehicle was stone cold and the outside temperature was 10 degrees. Cold oil is more viscous, and therefore it takes longer build pressure. Also, when I change the oil, I doubt the oil pump has any problem losing prime. Not so sure about the situation when the oil leaks back through the anti-drain back valve overnight.

Maybe it was not the anti-drain back valve, but the Ford mechanic emphasized the need to use an FL-820S Filter on the engine instead of the older FL820 or any other filter that did not use a silicone anti-drain back valve. The only noticeable difference between a FL820 and FL820S filter is the anti-drain back valve material (the "s" uses a silicone anti-drain back valve instead of nitrile).

And finally, I never had the problem when using an FL820S oil filter (more than 120,000 miles after the time I had the noise). I certainly can't say for sure the oil filter was the casue of the concern, but it seems Ford when to a lot of trouble to update the FL820 filter to include a better anti-drain back valve. I can't imagine Ford spending an extra penny for something that was not beneficial.

Ed

About what?

Who said it wasn't. His interpretation of the facts are what has been questioned.

All of them are as far as I know.

Why because that supposition supports your fictitious and superstitious beliefs?

If no air can be drawn into the filter from the outlet side, then no air can get into the filter or any of the plumbing from the stand pipe to oil pick up in the sump. No air anywhere in the system from filter to sump means no oil pressure problem that you guys were having. The symptoms you describe are either due to air in the system where there isn't supposed to be air or a blockage in the system such as the anti-syphon valve in the engine sticking. That was a problem that Chrysler reported happened in some engines. There are at least a half dozen different ways that air could be getting in the system. For instance, there are a bunch of gaskets between the oil filter and sump that could leak and allow air into the system. And some of the others ways have already been discussed.

Bah humbug. And I suppose you believe in Santa Clause?

That statement is false.

(note:

That may be a fact but you have no evidence it is relevant to your claims. All these filters are ISO tested including the ADBV. Where is the evidence from those test that the material makes any difference? Someone who chooses to ignore the test evidence and instead rely on idiots who have only eyeballed the guts of a filter is superstitious IMO.

Even when it was -32F the rubber in the Fram filters did not fail. I know they don't fail on engines that are working as designed. I know others had the same experience as I had. That means I have believable evidence 1000's of these filters were known to never fail a single time. You want me to believe that your experience with a couple filters where you think they failed is going to be more convincing then my experience. It is just not very likely that you got all the bad filters and I others I know got only good ones. A person would have to be superstitious to believe that.

No you didn't. You had an oil pressure problem and a rod knock which you said persisted even with the WIX (only not as bad). You described the problem clearly enough. It is your interpretation of the cause that is lacking.

No body has called me on anything. You have superstitious beliefs about what you think is going on in places inside the engine you can't see. These engines when working properly do not have low oil pressure problem you say they are prone to. You even admitted the WIX filter didn't completely fix the problem but just improved the symptoms. I don't doubt that, but that isn't evidence of a bad filter it is evidence of a problem with the engine that was misdiagnosed.

-jim

Wix doesn't calim to use a silicone anti-drain back valve on all filters. The Wix advertising copy that shows a silicone anti-drain abck valve also includes a disclaimer that says "Some filters may or may not have these specific features due to OE requirements or other manufacturing processes. Refer to individual part numbers for specific details." Unfortunately the individual details available from the Wix website does nto include this information.

And Fram does offer filters with silicone anti-drain back valves, you just pay more to get them (the Tough Guard product line).

Ed

I suppose you believe in order for me to become not an idiot I would need to have an engine with low oil pressure and spread folklore tales on the internet about how my engine got to be like that? I guess in your mind, everyone who is not having that experience is obviously demonstrating idiocy.

It's not hard to see why you would be concerned about finding a good mechanic. With your superstitions it would be just as hard for you to determine if a mechanic was competent to fix your problems as it would for you to figure out what is wrong yourself.

-jim

superstitious

sludge/residue

You're an idiot. No use wasting any more electrons on you. Go ahead and use your s***ty orange cans, I don't care. I just hope you're not a real mechanic and never do any work on any of my cars. I'd like to say that that's impossible, but I *have* seen some really incompetent "mechanics" out there.

nate

That same one who continually occupies your mirror?

Depends on your goals. If you want the minimum upkeep, and you run the vehicles a relatively short time, and then just want to auction them off, you are probably right.

If you want to maintain your warranty and run the car for 8-10 years and

At least, that seems logical to me.

Oil is damn cheap compared to an engine.

We keep them a long time. There simply is no meaningful benefit to changing the oil more often the 6/6000 except in VERY unusual situations. There is NO ONE who in the past 20 years has documented any benefit to what you are doing and I'd be shocked if you could find a professionally managed fleet that uses 3/3000 intervals.

And for the most part they all say around 6/6000. Some claim you need it more often for taxi service but Consumer reports proved that is not needed.

You can spend your own money any way you want but there is no factual basis for your claim that such frequent oil changes are any benefit. You are still living in the world of 1960 oil.

USPS does for many of their vehicles. Of course, they beat the crap out of them. There are other exceptions, I am sure, of what you say above.

But, for the most part, you are correct.

I hate to be picky, but what Consumer Reports says about taxis is not relevant to most people.

For some vehicles, besides postal vehicles, need more frequent changes. But for the vast majority of the cars people in Europe and North American drive, 6/6000 is enough.

Jeff

You really don't understand viscosity, pressue and flow do you.

Ed

My 1997 Lumina owners manual has 2 schedules for oil change. Short Trip/City - 3000 miles or 3 months, whichever comes first. Long Trip/Highway - 7500 miles or 12 months, whichever comes first. What that means is beyond me. Let's say I change the oil, drive 1500 highway miles to my vacation city, drive 500 miles in that city, come home 1500 miles on the highway, and then do the typical city commuting again. When do I change the oil? Stupid to try to make sense of that. Easier to just change the oil every 3000, or 5000, or 7500. Pick your own number. That CR test on taxis was full of flaws, the obvious one being that taxis often run all day without being shut down. Anyway, nobody knows the real difference of changing at 3000 versus

--Vic

I know all that, but that's not what the manual says. It says exactly as I stated.

What, by quoting some Joe Blow at Edmunds? Hardly "Scientific."

They don't even have that right. My car gets to operating temp in no more than 3 miles, even when it's -0 F outside. Beside that, many use their car for long commutes, then jump into them at night or on the weekend go a couple blocks to pick up a gallon of milk or something, never getting the engine warm. Repeatedly.

No surprise that oil companies want to sell more oil.

You just pick an acceptable duration - to you - according to your judgement of what facts are as you see them. BTW, using the above logic, why change at 7,500 mile? Why not 15,000, or 30,000? After all, you're just forking over money to the oil companies. As I said, NOBODY knows the difference 3000 vs 7500 mile oil changes have on the engine in the long run. NOBODY. Even somebody who gets an oil analysis done every change doesn't know the actual effects of those results. Let common sense be your guide if you have no scientific data to back up your inclinations. My mark is 3000 miles, but I'm not religious about it, and sometimes go to 4000. It's not a big deal. The oil gets recycled.

--Vic

I like the GM system for determining oil change intervals. It is not perfect, but it does at least attempt to modify oil change intervals to compensate for varations in the vehicle usage. I had a Saturn that used it. I never actually waited until the oil change light came on, but with the light providing a stop point, I felt a lot better about extending the oil change interval.

For most of my life I have been a 3000 mile oil change guy. But after seeing how well things went for people I know who change at longer intervals, I decided to go for longer intervals as well. I figure for everything I own,

Changing oil too often is not cheap insurance if there is no benefit.

Ed

I only mention it because the car makers love to stick that in the car manual as "severe severe" when it's clear that it's not.

Obviously, they do. However, the vast majority of engines do not build up sludge like that. And, the parts shown are not visible from the outside of the engine. How often should the engine had its oil changed?

What you're making is a straw man argument. You have yet to explain how a mechanic is supposed to know how often to change oil. It is obvious when there is a bunch of sludge in the engine that it should have been more often. But you haven't said how to determine how often.

Now that you mention the GM system.... My 95 Caprice had that in it. We changed the oil, per our fleet policy, every 6000. The oil change light came on almost always about 500 to 1000 miles sooner, IF it came on at all, between resets/oil changes. So based on that I'd say the GM algorithm came pretty close to calling for a 6000 mile interval.

I don't know how that determines a change is due. The manual says it could come on in as little as 2000 miles - or less!, depending on some "conditions" mentioned - speed, temp, etc. My son does my oil changes, and I suppose he could have reset it at some point. I'll have to ask him, but I don't think he ever reset it. The manual is vague, only saying that it should be reset after changing the oil, but not specifying that the light actually on requires the reset. Reset is key in run, engine off, push accelerator to floor 3 times quickly, and light should blink twice and go out. Anyway, the light is on now and has been since we got back from Florida a couple months ago. We changed the oil before we left, and only put about 3000 miles on it before the light came on. First time I ever saw it, but since my wife is its main driver, I'm not sure if was on before.

--Vic

No, the argument with the picture of the sludge-filled engine is part of a straw-man argument.

Correct, because a mechanic is not supposed to know how to determine how often to change the oil independently, but, rather, follow the manufacturer's recommendations.

Jeff