The bypass to a pressure resistance in the cooling loop is external tubing on the transmission itself, where a pressure valve activates and allows outgoing fluid to immediately return to the input port, allowing continued lubrication of gears immediately therein.

Ford feels that the lack of lubrication to these gears is more important to address than a rise in temperature caused by a lack of flow through the coolers.

Pop

 

David, now that you've added the Magnefine, you've added another potential point of restriction that you can easily test.

The Magnefine has it's own internal bypass. It can get stuck in a partway position and impede flow. There are knock off Magnefine filters in market circulation that apparently are far more prone to creating restrictions in fluid circulation. This inline filter, whether genuine or fake, could be responsible for the higher temperatures that you are noticing.

However, two things I am reminded of.

1. 175 degrees, even if higher than what you've seen in the past, is not overheating, and is actually quite close to an ideal operating temperature, according to Mark K.

2. As the month of May comes to a close, we are transitioning into summer and higher ambient temps, which can be a misleading time to make before and after comparisons


If you give me a few hours, I'll photograph a fully disassembled Magnefine filter for you.

And yes, I'd be delighted to receive the carnage of your other filter to personally examine. Thank you!

In the meantime, to see if your new inline filter is restrictive, can you conduct a quick one gallon per minute (one quart per 15 seconds) return flow test, post Magnefine filter?
That was the procedure Ford required after every inline filter installation... to verify adequate flow through it before releasing vehicle.

 

Interesting. Thank you for the update on the bypass.

I guess I can pull the filter and try to run straight through and monitor the transmission fluid temperature.

If I still see 175F without the filter, I'm guessing it's just normal (for my truck) and can reinstall. If not, I can re-explore other filtering options, including a replacement Magnefine filter.

 

Assuming the inflow from the transmission cooler is not under pressure, I assume I could test by pouring into a funnel, attached to 3/8" clear tubing, and into a measured bucket. I have synthetic transmission fluid laying around, but at $10/quart, that's an expensive test (but not more than the cost of a new transmission).

If it is under pressure, could I simply TEMPORARILY replace the rubber 3/8" transmission fluid hose that runs from the outflow of the new filter to the metal tubing and watch the flow. QUESTION - does fluid flow while the truck is in Park? If not, watching the flow through the clear tube might be a problem. :-)

 

No no no don't do that.

Driving it, with or without the filter, is not going to give you enough information that you really need.

You have a gauge for temperature. You don't have a gauge for FLOW, and that is the info you need to determine whether your oil to air transmission cooler is plugged with fine sludge, or whether your new inline filter is one of those wonky ones that isn't functioning right.

You can't conduct the flow test on the road with your current gauge set up.

Last I checked on the price of a flow meter for some industrial equipment, it was a lot more expensive than a one quart container, a two gallon bucket, and a few feet of vinyl tubing.

Do the flow test. I'll post some specific instructions in a minute, but I'm stuck on a call right now. I just saw your post and wanted to jump in here real quick and advise that you pursue a different plan that is a lot less work than the series of drive cycles you had in mind.

 

Ok, David...

Going back to your first post in this thread, and looking at the picture of the installed Filtran inline filter... we want to disconnect the hose clamp attached to the OUTPUT side of that filter, and attach our own line there in lieu of the existing return line to the transmission.

We are going to route our own line to the one quart container, and have the two gallon bucket standing by to dump the contents of the container in when the one quart fills up (which should happen in 15 seconds or less).

That's the executive summary of the test. Fairly straightforward.

Now, to refine some details here and there.


1. Get a friend, a neighbor, a wife, a girlfriend, a lawyer... anyone who will do what you say on your command immediately. OK, that probably rules out 3 out of 4 people suggested above, but the point is, find someone. It will go a lot faster. All they have to do is start the engine, and stop the engine, allowing you to wrangle your buckets and tubing.

2. If no one is around who will do what you say, all is not lost. There are dahls to solve that problem. I'm talking about Dahl tubing clamps. Or pony clamps, or clothes pins, or bar clamps. Anything that will secure your add on tubing to the side of a bucket so that it doesn't spill all over the place. Increase your bucket size to 5 gallons, to make it more stable if by yourself.

3. Obtain a 10' section of 3/8" ID clear vinyl tubing. This will go from the OUTPUT of your inline filter, to your 1 quart measuring beaker (an old juice bottle works for that) and to your 5 gallon overflow bucket when you are not measuring but need a second to shut the engine off.

4. Use two drip pans... one under where you make the connection at the inline filter, and the other under your bucket location, which if by yourself should be right beside you on the ground at the fully opened driver's door.

5. Have a couple of worm gear hose clamps handy, in case the existing hose clamp on the short length of hose attaching your inline filter to the hardline has taken a "set", embedding itself into the hose, and you don't want to disturb it. An extra clamp allows you to leave the existing clamp in place, and just use the new clamps for your flow tests, of which you will be conducting two, if the first test fails.

6. You'll need some new transmission fluid. I'd get a gallon, maybe 6 quarts. But I'm clumsy, over prepare, and under perform. You might be more efficient and get away with having less on hand. I prefer synthetic Mercon V. Mobil 1 has been trouble free in my experience, and meets Ford's specifications for this transmission.

7. Arrange those quarts in such a way that they can be readily poured back into the transmission. One of the most important reasons for limiting the flow test duration to only a 15 second interval, is due to the fact that the fluid measured in your test is NOT returning to your transmission. It is going into your measuring quart container, and when that gets full, into your 5 gallon pail. You'll have to add fluid back yourself. If the buckets are pristine clean enough, you can add the removed fluid back in, but that can be quite disruptive if you need to do a retest due to a failure in flow, or forgetting to note the second the test began. (Guilty) So I just leave the bucket on the drip pan and pour in new fluid. It's easier, and cleaner for the trans.

8. Either way, you'll need a funnel in place at the trans dipstick.

9. Place a stopper in the return line to the transmission, from where you removed the output of the external filter. That's another reason to have a couple of extra hose clamps for the test, so you can use the existing hose clamp to secure a 3/8" short bolt into that short rubber hose that normally attaches your inline filter.

10. This is just a place holder, because I'm sure I've overlooked something before you turn the key and begin your first flow test. Besides, Dave Letterman always had lists of 10.

11. NOW THE TEST. With drip pans in place, clear vinyl tube attached to inline filter output, plug attached to return line, clear vinyl tube clamped to 5 gallon bucket at your feet by the driver's door, leaving a short lead inside that bucket to slip your measuring beaker into, a long funnel pre inserted into transmission dip stick tube, and some fresh transmission fluid standing by, I think you are ready to turn the key...

12. Start the engine, and then wait before timing your 15 seconds into the quart container only until after you see a full line of bubble-less transmission fluid steadily flowing out of your clear tube into the larger bucket your clear line is clamped to. Once fluid flow reaches steady state, transfer the short leader of clear house into your quart container. If that quart fills to the brim within 15 seconds or less, you are done. Your transmission cooling circuit, as configured, passed the flow test. If it takes LONGER than 15 seconds to fill the quart container, then stop the test. We've got more work to do.

13. SECOND TEST: (If first test failed) Dump the quart contents into the 5 gallon bucket, disconnect the clear vinyl tubing from the inline filter, and remove the inline Magnefine filter altogether.

14. Obtain a male to male inline nipple to substitute for the Magnefine filter you just removed. Re attach the clear vinyl tubing to this nipple. The idea here is to determine if the test failure was due to the Magnefine or not. If the next test passes, it is highly probable that the Magnefine filter is defective. This would not be the first time that has been discovered.

15. Conduct the test following the same procedures as the first test. If it now passes, ditch the filter, connect your lines, and call it a day.

16. If the flow test fails even without the filter, then we have two suspects... a plugged Oil to Air transmission cooler, or a stuck cooler bypass valve on the outside of the transmission itself. That's what Pop was talking about in an earlier post.

If you get to this point of not passing the second test, it's time for a new post, with a new game plan to get your flow on.

 

How would pouring fluid through a funnel test anything? I might as well test my Lincoln and send you the results. It would be just as useful to you, and you wouldn't have to do any work.

The fluid does flow in park. Fluid in the line is always under pressure when the engine is running. That is necessary to have flow. If there is no pressure there is no flow.

Why would you watch the flow? Can you see if it is flowing a gallon per minute you looking at it? I don't know how to do that.

 

Thank you. My unfinished thought which I failed to include in my post was: funnel connected to 3/8" tube connected to my new Magnefine flowing into a measuring bucket for 15 seconds.

Given your and the above posts, it now seems that this process won't work.

With regards to the clear tubing after the Magnefine, I was thinking about a total blockage at the Magnefine filter. If I didn't/don't see flow, I think it would be fair to say the new filter is clogged.

You fairly pointed out that I couldn't measure flow, and I will be following Y2KW57's procedure in the coming days.

Again, thank you for your feedback.

 

Or the OTA cooler is plugged. Or the CBV is stuck. You can't know until the second test, if the first test fails.

If the blockage is upstream of the Magnefine, how would you know it was just the Magnefine by only measuring after the Magnefine?

That's why the test is multi staged.

Technically, we really should be pulling the return line at the transmission itself. But I saw your pic, with the hose clamps so easily accessible right there, I figured we could give the last section of transmission return line between the inline filter and the pan a pass, so you wouldn't have to fuss around with the transmission fittings unless the other two tests failed.

Rule out the magnefine first... but that doesn't get ruled out in the first test. It only gets a fail if the second test passes, with the Magnefine removed.

I hope you understand the layered distinction.

 

Let's make this simple.

Get five gallon bucket, spotlessly-clean.

Get one quart jar, also spotless.

Place jar in bucket.

Get length of 5/16 tubing (fuel line is OK).

Find the LAST thing in the cooling circuit before it goes back to the transmission (in your case the output from the Magnifine)

Put one end of the hose on that last thing's output port.

Place the other end in the jar.

Get in and start the truck, let the engine run for exactly fifteen seconds, then shut it off.

Get out and look at the jar. Is it full or over-flowing? You're good-to-go.

Is it almost full? You're probably still going to be OK.

Is it woefully short of being full? You need to find some restriction in the system.

Dump the fluid back in your trans (unless you see some crud floating around in it).

Pop

 

+1 ^^^

Tried to rep Marv...

 

Too small. That will cause restriction and cause this test to always be a failure. Use at least 3/8".

Don't like that, either. The cooler lines will usually drain back into the trans with the engine off. So the first several seconds is spent refilling the lines. If it drains enough, most of the 15 seconds will be filling the lines and cooler and there will be very little fluid coming out.

That's why when I wrote a procedure to do this I had two clean buckets. The line is in one when the engine is started. Once the flow is steady the line is moved to the second bucket for EXACTLY 15 seconds, then moved back to the first bucket and the engine turned off.

 

Of course it's 3/8-inch line.

Previous vehicles I've owned used 5/16" for cooler lines, but the SuperDuty in the driveway is 3/8".

Wonder why I missed that? Hmmmm.... OFS? "CRS" any more!

Pop

 

Not always so "simple" is it?

To think of every step, and every possible misstep, and every possible misinterpreted step, for every level of experience, is challenging. Even without CRS.

The devil is in the details. I did say to wait before timing the 15 seconds until a full line of bubble-less fluid is flowing first, and did suggest having two catch containers... but even that could have been misinterpreted by someone who hasn't done it before, because I didn't specifically mention to hold the tube in the larger bucket until the bubble-less steady flow is reached, then transfer to the quart and start timing simultaneously.

To those with lots of experience, some steps may go without saying. But no experience is required to do this simple test, so to be of the best help to all readers, no experience is assumed.

 

There way is the easiest I've found:

*** Transmission must be up to operating temperature to perform this test on the 4R100! ***

1. Place one gauge in the test port of the 4R100 on the drivers side ( use a six foot line so the gauge is in the vehicle while I'm seated at the Wheel.

2. Place a 3/8" "T" between the Filter and the return line. Ensure there are no kinks. The line may be looped but not kinked. Attach another Gauge to the "T" using 3/8" Transmission Line.

* Use Approved Transmission Line as the hydraulic fluid can breakdown materials used in other applications and contaminate the system You only need a six feet so it can be in the cab with you where you can monitor both gauges *

For each position (Selector) there is a specific pressure the pump emits . You can find that in the FOMOCO WORK SHOP MANUAL. Ensure the return readings are within 10% of the Pressure line readings. If you're not getting the specified head pressure at the test ports this is an indication of internal failure of either the pump or accumulator valves.

For Example: 60 PSIG Head Pressure at the Transmission Port should read no less than 54 PSIG on the return line. Anything greater than 10% indicates a blockage - severity is relevant to pressure drop. It is a closed loop system or the by-pass valve is malfunctioning.

COLD: You can also test the By-Pass valve operation by putting the "T" prior to the cooler. You should read no, or just a few PSIG.

HOT: (At operating Temperature) There should be no drop in pressure.

***If your doing a stall test DO NOT allow each test to run for more than 15 seconds with a cool down period. Internal damage to either or both the converter and transmission may occur!

*** There will be transmission fluid in the lines of the test equipment. Be aware when they are disconnected it will run out on to the ground. So keep the connection ends higher that the gauges to prevent spillage.