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Transmission fluid or not!

OldButStillJeeping

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Wrong, on a cold engine and transmission like overnight sitting cold, fluid will drain back out of the torque converter and being above the fill hole line. When you remove the fill hole plug, that fluid will come out and level out at the fill hole. That remaining fluid is either sucked out the fill hole or exits when the pan drops.

Like I said, I have done two of these transmission pan drops and filter changes and both times, fluid came out when the fill plug was removed.

Shown similar here:

Perfect. That vid alone was worth the price of admission.

A Honda / Acura tech working on a / his gladiator... Priceless.
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Stan H

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Most do a contract deal with Safelite and get heavy discounts. It's like health insurance scamming - the doctor's fee is 1200, insurance says nope, you get 250 and it's settled.
Insurance companies and service contracts cut their costs by doing the same - we'll use you EXCLUSIVELY if you agree to these rates.
Yeah 🎯 you are probably 100% correct and to top it off the safelite installers around here are terrible to deal with.
 

Maximus Gladius

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You can go a lot longer than that on just a change with modern fluids.
The question I’ve had lately, because of much discussion to do early changes or leave it to ride out to end of warranty is, when does varnish start to show up on the clutch plates? I know there’s external factors that can speed up this process that cause more heat but when does varnish start? I haven’t seen this question asked.

I’ve also read your comments about long running transmissions that have been left alone “can” do just as well as those where oil changes have been done so there’s really no good reason to do changes till you’re around 50k or so miles.

When expressing your opinion or feelings on this, I read it like the statement is a guess and not a scientific, mechanical fact. We’ve measured these plates and compared one set to another or we’ve seen the varnish on one set and compared to another with similar milage but one was cared for and the other was not? I for one would love the data. I’ve never looked at transmissions opened up to see the causes of varnish, non care vs care.
 

ShadowsPapa

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The question I’ve had lately, because of much discussion to do early changes or leave it to ride out to end of warranty is, when does varnish start to show up on the clutch plates? I know there’s external factors that can speed up this process that cause more heat but when does varnish start? I haven’t seen this question asked.

I’ve also read your comments about long running transmissions that have been left alone “can” do just as well as those where oil changes have been done so there’s really no good reason to do changes till you’re around 50k or so miles.

When expressing your opinion or feelings on this, I read it like the statement is a guess and not a scientific, mechanical fact. We’ve measured these plates and compared one set to another or we’ve seen the varnish on one set and compared to another with similar milage but one was cared for and the other was not? I for one would love the data. I’ve never looked at transmissions opened up to see the causes of varnish, non care vs care.
My "opinions" are based on college training, production shop work over years, decades of experience in automotive in general, automatics included, hand-on hundreds of transmissions not my own, and over 50 years of ownership of many vehicles. That "opinion" is going to be based on more than almost any other here other than a tech or a person trained and experienced with such things. So in other words, I'll take my "best guess" over anything else here unless it's from a scientific view, factory training and so on.
Do you know what perceptual reasoning is? Maybe look it up but what you get in Google is only generic stuff. A fraction of the real explanation and real life (and it varies wildly with the person)

To lump the "opinions" of a factory-trained, college-trained trophied tech with that of the general internet is just plain an insult. Observation and experience.

When does varnish show up? LOL - see, you ask black and white questions looking for a definitive answer based on miles. When will you get cancer and what type? Or will you?
How long will YOUR tires last? Give me an exact number of miles - and say ok, then every Jeep owner with those tires will see the same miles.

You want to know about the "onset of varnish". Some won't see it, some will, some bad, some early, some later. It's about HEAT and oxidation - and of course will vary with the transmission, the use and the FLUID used. It's like oil - some will go 10K and still be fine on their oil, some will need to change much more frequently. You just can't give a solid answer.
Heat is a huge factor. You might say "well, then, anyone towing". No, not necessarily. Depending on how, what and where you tow and how FAST you drive will matter. If I tow watching the temperatures, use manual mode when called for and keep my speeds under 65 I can tow a lot and not need a fluid change nearly as soon as someone who runs hot and fast.
My 95 F250 towed a hellish heavy load. I had a 15,000 pound receiver and towed a flatbed that was over 3,000 pounds empty. No brakes. I hauled tractors and farm equipment, and hauled a car through the mountains of PA with that thing. 70K miles I decided on a fluid change. It really wasn't bad, and no sign of varnish. I was pushing it, I'm sure - probably should have done 60K, but still, it was fine. In fact, the transmission in that truck was the best thing about it. The engine was a wimp. The suspension sucked (bad wobble at 80,000 miles) but the transmission was solid - and no varnish, no shifting issues at all. Handled mountains and hills and towing and hauling over a ton in the bed just fine. I didn't get it HOT. And - it didn't get short drives, either. I've seen rust in automatics - constant short drives, never getting warm enough to bake out any humidity.

The problem with Jeep owners and transmission fluid is that it's almost like a right of passage, among other things. (so maybe I should get ahead of the curve and do mine every 10K - just to prove I know better?)
They see all this talk out there - based on??????????????
Then someone who actually has experience and training out there questions their "science" and suddenly you might as well have put a duck on their Jeep - you've questioned something about their very being as a Jeep owner.


Kirk:
Mr. Spock, have you accounted for the variable mass of whales and water in your time re-entry program?
Spock:
Mr. Scott cannot give me exact figures, Admiral, so... I will make a guess.
Kirk:
A guess? You, Spock? That's extraordinary.
Spock:
[to Dr. McCoy]
I don't think he understands.
McCoy:
No, Spock. He means that he feels safer about your guesses than most other people's facts.
Spock:
Then you're saying...
[pause]

Spock:
It is a compliment?
McCoy:
It is.
Spock:
Ah. Then, I will try to make the best guess I can.
McCoy:
Please do.

And finally -

Jeep Gladiator Transmission fluid or not! 1746976403016-tj


Since I am in tune with my vehicle, very observant of conditions, and know what I'm doing ,it's absolutely no issue at all for me, even towing, to go out to 60K or even 70K. If I decide something has changed - like heavy plow use, or transmission temperatures over my norms, I can drop that back to 50-60K and not sweat it a bit at all. it's called experience - hands-on, and training.

You do you - but actually, most of what's in forums is fear-mongering, or some "jeep thing" or right of passage or whatever, or a "look what I did" in a few cases.
Believe whatever you want to believe. If it's the infinite wisdom of the internet and the thousands of extremely experienced people trained techs and so on (HAHAHAHAHA) go for it. I don't care.
I'm just trying to get facts out there so the others don't scare the shit out of someone who went over 30K on their fluid!
 
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ShadowsPapa

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I found the novel "War and Peace" a shorter read.
(but people watch 15 minute videos with half of it marketing, music, or swapping phone positions LOL)

When someone asks about a complex chemistry question - or someone asks for a black and white answer, a given number, for something based on dozens of variables.................and they really don't understand even the most basic bits...... ever been through chemistry classes?

"varnish" (or even sludge) can be caused by mixing fluids.
Another reason that since you never change ALL of the fluid at one time, I stick to the ZF or MOPAR stuff.
People want a short fast hard answer for something that takes years of classes and experience to learn. Can't accept that "it's not that simple" or "based on miles".

introduce a new oil with a different additive formulation from the existing oil, the additives can react with each other, which upsets the lubricant and starts the process of degradation that ultimately leads to varnish.

Here's a bottom line from an article on lubricant varnishes - the article this comes from is a whole page long in itself:

Varnish is a complex subject and this brief overview barely scratches the surface.

And people want to attach a mileage or time or some other simple condition to it??
 

Maximus Gladius

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Here's a bottom line from an article on lubricant varnishes - the article this comes from is a whole page long in itself:

Varnish is a complex subject and this brief overview barely scratches the surface.

And people want to attach a mileage or time or some other simple condition to it??
I figured it was a worthy question, that’s why I asked it. I’m glad it’s not so easy to answer. It validates my unlearned question, notwithstanding you needing to club me with all your trophies and decades of learned knowledge, I’m not stupid or crazy for asking. I’m a master at spectating which follows critical thought. How does someone like me come up with a question on “when does varnish show up on clutch plates”, when I’ve never gone to school for it nor have ever seen inside a transmission, stripped down on a table in front of me? Think way back to your early years in “mechanical class”, pick one, did you ever raise your hand to ask a question besides needing to go to the bathroom? Did your prof take offence when you asked or come over and clobber you with his degrees?

If my question is like…IDK..”how long is a piece of string”? Then it’s as you say, it’s complicated, there’s no simple answer and time and miles to varnish is not the same for everyone so,…..then the parameters set by ZF or Mopar when to change shouldn’t be the same for everyone.

Ok, you should know by now if I ask you a question, it’s because, #1, you will mostly likely know the answer because of your life long mechanical accomplishments and knowledge and; #2, I asked because when the topic of when to change oil is discussed, varnish is never mentioned, except maybe it is briefly when the odd and rare reason to not change the oil in a “high milage” transmission is because the ‘debris in the oil is what helps the clutch packs work properly (I’ve mentioned hearing this before) you’ll recall answering that post with ‘I’ve never heard that reasoning in all my transmission tech years’. I’n fact I was reading some other post recently on transmission oil changes and this reasoning was said again. It’s actually a thing and “some” believe it,
correct or not.

You did however say you’ve never heard it but suggested maybe varnish is to blame so changing the oil and transmission clutch slipping is a result of the debris washed out. ??
My question(s) to you about things are never asked, to insult you. That’s not who I am but I have come accustomed to suiting up with armour to prepare for your incoming trophies you need to hurl. Too bad this has to be experienced by so many. You can and have the ability to answer very well and respectfully and there’s a few here, that can and have learned much from you.

So, back to chemistry, and best practice for long life, ZF does loosen the reigns to changing oil “early” or at times not stamped in stone when “you don’t know the history of it”, when running hot, when it’s contaminated etc and it even tells you to “check”.

So “checking” is suggested but ZF doesn’t tell you how. God forbid you pull a sample and have it lab test wear metals and oxidation test. Maybe doing a “sniff test” or “dip your finger in the fill hole and rub them together test”, IDK, MAYBE a little varnish is ok like a little bit of cancer is ok or smoking little cigarettes is more ok than big ones.

I’m going to ask my lab tech to run oxidation tests on my transmission from time to time and IF varnish has markers that can be detected without having to do a tear down to visually see, I’m going to find out and share that knowledge here. I hate guessing and assuming, I like the cold hard data points. Maybe doing this might shed light on the whole complicated world of varnish and not letting it form in the first place.
 

ShadowsPapa

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I’m going to ask my lab tech to run oxidation tests on my transmission from time to time and IF varnish has markers that can be detected without having to do a tear down to visually see,
If they can run tests to determine oxidation, that would be great.
There's a lot of crap floating around out there about ATF.....
For example "put some ATF in the engine as it's higher detergent and will clean the engine".
WRONG. ATF is far lower detergent, very little.
Engine oil is far higher detergents and is formulated to carry contaminations around to the filter.
ATF is formulated to DROP things out of suspension - into the pan.
So you actually want to see the gray crud at the bottom.
Engine oil you want to carry them in suspension to the filter.
Millions of transmissions with no filter (not counting the screen), the contaminants need to settle to a quiet area.
So if you do a flush, you get all of that crap that's settled into "quiet areas" stirred up, some of it has gotten semi-solid.

ATF is made for a semi-closed operation - if they could do away with a vent it would last far longer than it does. High heat allows the fluid to oxidize - the moisture in the air in the transmission is part of that formula.
One reason a dipstick was eliminated was to get rid of a way for air - and thus moisture - to get into a transmission. This alone allowed the fluid to last a lot longer than past years.
 

Maximus Gladius

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If they can run tests to determine oxidation, that would be great.
There's a lot of crap floating around out there about ATF.....
For example "put some ATF in the engine as it's higher detergent and will clean the engine".
WRONG. ATF is far lower detergent, very little.
Engine oil is far higher detergents and is formulated to carry contaminations around to the filter.
ATF is formulated to DROP things out of suspension - into the pan.
So you actually want to see the gray crud at the bottom.
Engine oil you want to carry them in suspension to the filter.
Millions of transmissions with no filter (not counting the screen), the contaminants need to settle to a quiet area.
So if you do a flush, you get all of that crap that's settled into "quiet areas" stirred up, some of it has gotten semi-solid.

ATF is made for a semi-closed operation - if they could do away with a vent it would last far longer than it does. High heat allows the fluid to oxidize - the moisture in the air in the transmission is part of that formula.
One reason a dipstick was eliminated was to get rid of a way for air - and thus moisture - to get into a transmission. This alone allowed the fluid to last a lot longer than past years.
Thanks for that! I know that I get the generic lab test to show wear metals but they can also dig deeper and provide further tests for an additional fee. I think it’s the oxidation test but will find out and I’ll ask the tech about varnish markers in a test and see what he says.
 

g2020

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The 4th of these four posts is more like War & Peace. The specific sections in the first three posts are quick reads. Facts are thoroughly documented back to manufacturer or licensor. Some advice is borrowed from experienced members of this forum.

1. Key Info on Fluids & Filters for Jeep Gladiator
- See Important Reminders | ATF for automatic transmission
- See Exceptions to Owner's Manual | ATF for automatic transmission


2. Links to Prices of Fluids & Filters for Jeep Gladiator
- See table in section 1.10.1

3. Warranty Coverage on Damage to Other Parts
- See ATF for the Automatic Transmission - After the Drivetrain Warranty Expires

4. References to ZF-Approved ATF Equivalents for 850RE Automatic Transmission
This post contains:
- Four documents related to ZF-approved ATF equivalents for the ZF 8HP50 / Chrysler 850RE automatic transmission
- Advice on ATF for the automatic transmission (and manual transmission) from the Jeep Gladiator owner's manual
- Key considerations on ATF for the automatic transmission


A few things I would add/repeat:
  • For normal driving (if normal is possible in a Gladiator), consider changing ATF for automatic transmission at 93K miles (or a bit sooner) and then every 93K miles (see key considerations above)
  • Whether a transmission service is performed by a dealer or an independent, it will essentially be a pan drop with sparkly new parts
    • In many DIY cases, the pan, gasket, and bolts can be reused; new ATF and new filter are required; for bolts to be reused, they must be steel and not aluminum, and be in good condition; use a magnet to determine type of metal)
    • A transmission flush is not recommended
  • Also see key considerations above for a discussion of Warranty Coverage
 
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Stan H

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    • A transmission flush is not recommended
  • If taking a small sample of ATF for testing, do it toward the end of its expected life because removing the fill plug to take (and then replace) even a small sample of ATF can slightly accelerate oxidation / degradation of additives
This I find hard to imagine seeing how if it was out during fill out it will make any difference if said transmission is cool and a small sample is pulled .
 

ShadowsPapa

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This I find hard to imagine seeing how if it was out during fill out it will make any difference if said transmission is cool and a small sample is pulled .
It's going to vary with the transmission and the time it sits, but if you wait for it to totally cool and sit for a length of time, the converter may drain back into the transmission meaning it could be more messy getting a sample.
There's a reason these are checked at a specific temperature, after running them, and through gears - fill the converter, expand the fluid an exact amount, make sure the clutch packs are filled and so on.

Sort of like the old days (with dipsticks) - you checked with engine running at idle and for MOPAR TF 727 904, 998 and so on, in neutral, pretty much all other domestic makes (Ford, GM) you checked in park.
This was to ensure converters were filled and so on.
 

g2020

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This I find hard to imagine seeing how if it was out during fill out it will make any difference if said transmission is cool and a small sample is pulled .
I am agreeing with the "HEAT and oxidation" comment in post #34 above. Removing the fill plug briefly exposes the fluid to more air than usual. Then again, when 3 fl oz is removed for testing and it is replaced by 3 fl oz of new ATF (resulting in a very slight increase in new additives), this ATF exchange might offset the brief increase in air exposure. Each of these amounts (air and fluid) are marginal at most. I have removed the comment on testing from my reply above. Thanks for catching this.

I should have said something like "test ATF only if you suspect that it may need to be changed", and left out the marginal / very small concerns. For those who don't know how to pull a sample of ATF yet, see the section on Testing at the end of my post on References to ZF-Approved ATF Equivalents.
 
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guntrust

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I believe my transmission fluid (manual) was supposed to be changed around 30K but my dealer forgot to do it and i was relying on them. We just noticed and changed it at 50K. Was worrying about this but it sounds like most everyone is getting by OK changing at longer intervals.
 

Maximus Gladius

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I have the lab doing an oxidation test on my transmission oil. They keep the old sample for 3 months so, since my transmission oil was pan dropped early April, they can pull my sample bottle and run this new test. They only needed me to bring in fresh oil to compare, so I ran that over to them.

I went in the back and met with the lab technician and he gave me the 15 min run down on the “markers” they look for with regard to varnish BUT….if the oil is a full synthetic, the synthetic spike is too high and wide to be able to find varnish markers. IF the oil is a semi-synthetic, chances are much greater to find varnish markers. He will tell me later today what he finds the Mopar 8/9 speed is. I told him I’ve seen where this oil has been called both semi and full synthetic.

IF he’s able to read the markers, then the data collected today will be compared with the next two oxidation tests and from there, can then draw a trend line with “time” and “distance” to determine when varnish is critical.

This testing goes beyond the typical generic test documenting wear metals and additives. My own pan drops are yearly, so in all fairness, a trend line can be made in 2 years.
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