[Doug D]

I remember my friend pulling the dipstick on the transmission on a 1980's vintage Ford and the trans fluid was gold. That trans was done.

Had a '93 Ford Aerostar where the transmission fluid was black. Was told it was the "black death". Anyway, changed the fluid and filter. It never turned black again. Transmission was still working fine when I traded it in (for a '00 T&C Ltd) with 203K miles on the odometer.

 

[ImperialCrown]

It is obvious that fluid color will tell you a lot about the transmission's condition. I think that the service manual statement about disregarding fluid color as a need for service was based on 'normal' fluid darkening with age. The darkening may be from fine particles of clutch material, which is normal to an extent.
Any metallic sheen or glitter in the fluid is an obvious problem.
Dark fluid combined with a burnt or acrid odor should also raise the need for further investigation, like slipping clutches and/or plugged coolers (note that ATF+4 has a strong, unique 'machine oil' odor and that is normal).
I have had vehicles with clean ATF on the dipstick still have a clogging trans filter. I wouldn't have known this until a pan drop.
Milky fluid is either coolant leaking into the ATF or water ingestion. ATF coolers still use engine coolant to regulate the transmission temperature. In cold weather, the circulating coolant and ATF in the cooler will exchange heat for faster ATF warm up. In warm weather towing or hill climbing with an unlocked torque converter, ATF temperature will soar and give up some of its heat to the engine coolant.
The auxiliary ATF cooler in front of the radiator is the air-to-oil cooler. Newer vehicles may have a thermostat to regulate flow through this cooler. Over-cooling or over-heating ATF is something to avoid, it should stay right around engine temperature.

 

[Doug D]

Over-cooling or over-heating ATF is something to avoid, it should stay right around engine temperature.

One feature I would like to see added to the gauge cluster is a temperature gauge for the transmission. Though I bet some customers might confuse it with the engine temperature gauge. I believe my '06 Ram 1500 has an "idiot" light that illuminates if the transmission overheats.

 

[ImperialCrown]

It is the amber or red 'gear and thermometer' icon for overheat. Many drivers don't know what it is when they see it.
Driver's that have had transmission failures may opt for an ATF temperature gauge. The controller software will recognize an overheat condition and default to a transmission protection mode: Radiator fan(s) on high, early TCC lockup, etc.

 

[ka9yhd]

Then on the opposite, A friend purchased a 1970 New Yorker and it had a very large aftermarket trans cooler mounted in front of the radiator. Which would never let the trans get up to operating temperature.
When was dissembling the transmission there was jello in parts of the transmission.

 

[CudaPete]

My 16 Cherokee has a screen option for Trans temp and one for oil temp. No oil pressure though, which I find odd.

 

[Rick Anderson]

Also, why not use another brand of ATF+4, why are giving up just because Pennzoil discontinued their ATF+4. Believe me, I would trust Walmart SuperTech ATF+4 way more than Pennzoil Synthetic Multi-Vehicle ATF that isn't ATF+4. There are plenty of different brands selling ATF+4 licensed from FCA, which means they are very much the equalvalent of Pennzoil or Mopar ATF+4.

Thanks for the advice.

You are confused about what fluid I would use and about what Pennzoil are selling.

They replaced the yellow ATF+4 container with a silver ATF+4 one that says "full synthetic".

If I decide to use full synthetic I can get Castrol, to heck with Pennzoil who were not helpful enough when queried.

I am looking for an older ATF+4 that is not full synthetic but that's now hard to find.

(I am very wary of WalMart because their products vary in quality, I've seen mislabelling.)

Ok, you're orignal post wasn't clear, it really gave us the impression you couldn't get Pennzoil ATF+4 anymore and instead wanted to substitute a generic Synthetic ATF.

ATF+4 is synthetic, any licensed ATF+4 product must be synthetic, and if it has ATF+4 on the Label (different than mentioning ATF+4 in the small print on the back) thus labeled as ATF+4 it has to be synthetic or FCA would have the company in court.

A lot of talk about fluids here;

There are two kinds of "Synthetic" oil, Group III and Group IV, Group III is mineral oil based, that goes through a synthesizing process to tailor the existing molecules more like the engineered molecue. Group IV is started from scratch using gases in a synthesizing process to produce a base stock all of the engineered molecule. Group III is much cheaper to produce, Group IV is better oil. But don't get the impression Group III is some pretender, its still superior oil to Group II, which is conventional oil that is just refined.

So perhaps the difference in Pennzoil switching is moving from Group III to Group IV base stock oil. Or more likely, Pennzoil is just repackaging the same fluid with new labeling to charge more or be more competitive.

BTW, if you want Group IV oil, don't go with Castroil, they are the ones that started the whole marketing Group III Oil as "Full Synthetic", when all the others were using Group IV. Castroil won in court when they were sued by getting "Synthetic" declared a marketing term, and because of that and consumer ignorance, they were making an insane profit margin and still selling like gang busters. So all the other company's joined them and switched to marketing Group III oil as Synthetic.

And Group III is different than Synthetic Blend, a blend is some synthetic oil and some conventional oil blended together. Group III is all conventional oil that went through a synthesizing process to make it very close to Group IV synthetic oil.

Ok, there are all sorts of applications for oil, just because one application uses a different type of oil than another does NOT mean its the best for all applications.

• Just about all brake fluids (especially the ones sold on store shelves) are Synthetic, just like the Anti-Freezes. When Silicone brake fluid first became available, it was believed it would be perfect, since it didn't absorb water and had higher boiling temps. And since it was a new chemical used as the base stock, perhaps people were calling it synthetic (while the old Glycol Ether was just as synthetic). But Silicone soon proved to be terrible, the fluid was compressible, making for spongy brake pedals, and the only thing worse than brake fluid absorbing moisture in a brake system proved to be a brake fluid that didn't absorb water. Any moisture gets in the brake system and it will, since it isn't absorbed, collects at the lowest point of the brake system. You get water bubbles in the line that start rust and rust a hole in the brake line, that bursts and you loose your brakes in the middle of braking.
• Jet/Gas Turbine engines were why Synthetic Oil was invented, since it had a higher heat resistance than Conventional Oil, that wasn't surviving in Jet Engines.

Synthetic and Conventional will have some different properties in some applications, one property might be more desirable over another, and thus in some cases conventional might be more desirable than another, and thus Conventional Oil might be better than Synthetic. It doesn't mean Conventional is better than synthetic in all applications. Wrankle engines, that have to inject oil into the combustion chamber, it is much better to use conventional oil, since you're going to be burning it. I guess conventional oil burns better with less coking or residue left behind than synthetic.

There's an Owner's Manual in your car, it lists the fluids the engineers tested in your car and found to work the best. So logically don't you think what they've tested and recommend is the best thing to use for your application, instead of saying to yourself, well some airlines have switched to conventional oil in their turbofan engines, so I guess I should switch from synthetic to conventional in my automotive transmission.

Now to ATF, ATF+4 has proven to be more durable and keep your 41TE lasting much longer than any other previous ATF+ version. And the previous versions were conventional oil base stock. Is anyone on this forum willing to tell the O.P. that his 41TE transmission is likely to last longer if he uses ATF+3 or other conventional transmission fluids? In the 41TE at least, its been proven Synthetic Based ATF+4 has made the transmission last much longer.

 

[Rick Anderson]

...Fluids do deteriorate with age, temperature, exposure and use. The additives that characterize a particular fluid do diminish over time...

Absolutely true, the only way a fluid can last the life of a vehicle is because even after deteriorating for 10 years or more, its still has sufficient properties to keep the system working and protected.

Some systems are low demand on their fluids, and don't deteriorate them as fast and also means they aren't so sensitive to the fluid and deteriorated fluid still works and protects. Other systems are the opposite, they are very demanding and wear out the fluid very quickly and will suffer damage if the fluid worn out.

What can happen:

• Contamination: Foreign Chemicals get in the fluid and react with it and break it down, form caustic byproducts that damages seals and metal in the system. This especially happens in Internal Combustion Engines, where the combustion byproducts work their way into the fluid and contaminate it. Its also why as sealing and tolerances have improved over the years, the interval between oil changes has grown. Less combustion byproducts are getting in the oil and contaminating it. Water always works it way into everything in a vehicle, it contaminates the fluids as well.
• Sheering: Oil gets it lubricating properties because the molecules are long chains of atoms, those molecules being forced between gear faces, or scraped off cylinder walls with rings, or run through a vanes of a pump, will break those chains. i.e. shear them in half. The more you use it, the more you'll break it down and less lubricating it will become.
• Oxidation: If temps get high enough the chemicals will react with oxygen, in a way burn, and oxidize which changes the molecules and breakdowns the oil.
• Naturally breaks down: There is a reason why things have a shelf-life, the naturally break down over time, some fluids in a vehicle this is true also. No matter how little you've used the vehicle, you may need to change the fluid simply for a time limit.

 

[Rick Anderson]

On my 2005 GC I drive with mostly city driveing I did a trans flush at the dealer at 60,000 miles. 70,000 miles later getting ready to do another.
I am amazed that chrysler recommends not to do it. What about G Caravan taxis? They get extreme use? I've always heard that if you keep your cars a long time (10 years) with alot of city driveing you should flush(drain) get new atf+4 in the trans.???????

What could happen to a transmission if it sucks in air and runs the pump dry or clutch packs dry? What could happen to a transmission if you back flow the fluid the opposite direction it was designed to go, or exceed the pressure that it was every designed to go in any particular circuit? And don't forget, a pump is stupid, if you increase the pressure at its intake, its output will go up a corresponding amount.

This is why Chrysler/FCA put out a TSB recommending against fluid flushes in their transmissions and systems.

The Owners Manual has a service schedule in it, and has an alternate "Severe Duty" schedule for things like Taxi and Fleet Service, with a more often transmission fluid change interval.

The engineers have tested this, and they have found, if you change the fluid at the recommended interval with the recommended fluid, you will replace enough old fluid with fresh to keep the transmission operating properly and well protected. This strategy is more likely to keep the transmission running properly for the longest time, than using some flush system that forces fluid through the system in a way the transmission was never designed to handle.

Now, what people often ask, what if I buy a used mini-van that never had the trans serviced and is way, way overdue..... Yes, that's a tough one, cause arguably changing only half the fluid that's in the pan might not be enough to keep the trans protected. That's why I suggested, either do the recommended service several times in the row, with enough driving in between to well circulate the fluid through the whole system. That would catch you up on the service, and get a lot more fresh fluid into the system. Arguably, you'd be draining a good amount of new fluid with the old on the successive oil changes, and tossing some money away.

You can disconnect the cooler lines and use Low Pressure Air (like 10PSI) to force the fluid out of the cooler while draining the pan, that can get you some extra capacity of fluid change, fairly safely.

There is the amateur flush, that not many people have screwed up and didn't cause problems. Where you disconnect the return line and put it in a bucket and fill the trans at roughly the same rate the oil comes out. You have to have a helper put the trans in gear. Again, you mess up and run the pan dry, you could damage the transmission.

 

[Rick Anderson]

It is obvious that fluid color will tell you a lot about the transmission's condition. I think that the service manual statement about disregarding fluid color as a need for service was based on 'normal' fluid darkening with age. The darkening may be from fine particles of clutch material, which is normal to an extent.
Any metallic sheen or glitter in the fluid is an obvious problem.
Dark fluid combined with a burnt or acrid odor should also raise the need for further investigation, like slipping clutches and/or plugged coolers (note that ATF+4 has a strong, unique 'machine oil' odor and that is normal).
I have had vehicles with clean ATF on the dipstick still have a clogging trans filter. I wouldn't have known this until a pan drop.
Milky fluid is either coolant leaking into the ATF or water ingestion. ATF coolers still use engine coolant to regulate the transmission temperature. In cold weather, the circulating coolant and ATF in the cooler will exchange heat for faster ATF warm up. In warm weather towing or hill climbing with an unlocked torque converter, ATF temperature will soar and give up some of its heat to the engine coolant.
The auxiliary ATF cooler in front of the radiator is the air-to-oil cooler. Newer vehicles may have a thermostat to regulate flow through this cooler. Over-cooling or over-heating ATF is something to avoid, it should stay right around engine temperature.

Yet, with ATF+4 its recommended, and I have seen it myself, to not judge the fluid condition off of darkening or smell. I know what your saying IC, and people do this with engine oil as well too much in extreme. They see some darkening and automatically assume the fluid is bad, its not. At the same time you can't go to the other extreme and look at the blackest oil you ever saw and say, don't worry, the oil is suppose to darken with use.

Out of the bottle ATF+4 doesn't smell bad at all, it also is very translucent pink/red. Within a short amount of use, way before the change interval is up, it will develop that machine oil smell. That smell is strong and acrid, and if you're not experienced you might assume that is what burnt oil smells like. As well, it doesn't take long for ATF+4 to darken up and become a much less translucent, purple color.

So while agree with IC, if your transmission fluid is black and smells like a smoldering campfire you just put out, there is something wrong and you've got to look into it as well as change the fluid. But be careful your not wasting time and money, cause perfectly good ATF+4 is going to look dark purple and have a strong smell to it.

 

[valiant67]

Then on the opposite, A friend purchased a 1970 New Yorker and it had a very large aftermarket trans cooler mounted in front of the radiator. Which would never let the trans get up to operating temperature.
When was dissembling the transmission there was jello in parts of the transmission.

The A604 had the same problem with fluid being too cold. Early on a device was added that restricted fluid flow out of the transmission to the cooler (whatever type it was, external or integral to the radiator) when the fluid temp was too low.

 

[Rick Anderson]

Fluid temp affects viscosity, viscosity affects pressure of the fluid and automatic transmissions need to have precise pressures to operate properly.

Electronic Transmissions can handle viscosity changes better, because they will adapt/adjust to changes that will come from different pressures. But it can only do it so much so if fluid got to cold it could affect operation. That's why they added a thermostat like device.

The old hydraulic automatic trans could NOT, and I remember stories of people with trucks using kerosene or an additive that was like kerosene in the winter to their older simpler truck automatic transmission to thin down the viscosity of the trans fluid to lower the line pressure when cold.

I had an '88 Plymouth Sundance with the old hydraulic A413 that I put a big trans cooler on it, cause I used it to tow a small trailer several times. And several very cold mornings, it did NOT shift right until I got the engine and trans warmed up to operating temp.

Remember, I mentioned Sheering, biggest thing with sheering is it reduces the fluids viscosity. So having good fluid at its spec viscosity will keep the trans operating properly, using degraded fluid that has much lower than spec viscosity could change shifts and pressure on clutch packs, etc and increase the wear and change the smooth operation of the trans. Although an electronic trans may be able to compensate at first. And it might be subtle enough not to notice if you're not looking/listening while driving, but you're wearing your trans faster.

 

[keithsketchley]

You haven't posted in months, but I well remember your posts that were argumentative for the sake of arguing. I stick to facts.

Synthetic brake fluid is rated for higher temperatures and is superior to DOT-3. Fact.


Dry boiling point Wet boiling point Viscosity limit Primary constituent
DOT 2 190 °C (374 °F) 140 °C (284 °F) ? Castor oil/alcohol
DOT 3 205 °C (401 °F) 140 °C (284 °F) 1500 mm2/s Glycol Ether
DOT 4 230 °C (446 °F) 155 °C (311 °F) 1800 mm2/s Glycol Ether/Borate Ester
LHM+ 249 °C (480 °F) 249 °C (480 °F) 1200 mm2/s [6] Mineral Oil
DOT 5 260 °C (500 °F) 180 °C (356 °F) 900 mm2/s Silicone
DOT 5.1 260 °C (500 °F) 180 °C (356 °F) 900 mm2/s Glycol Ether/Borate Ester

Rejected as unresponsive and trying to smear someone who is just trying to make sure of knowledge instead of guessing.

https://drhurd.com/2017/02/09/62912/#.WJy1iXJlw7c.facebook

 

[keithsketchley]

Thanks Rick Anderson, good point about characteristics being the key. However, what we don’t know is whether or not the “full synthetic” has been optimized for newer designs at the expense of older vehicles. (We hope Chrysler reduced sensitivity to fluid in later designs, but they were also under pressure to get fuel efficiency. That appears to have been a factor in the German car industry’s botch of engine oiling circa 1990.)


Rick, I am indeed having great difficulty finding _any_ ATF+4 in my area, Pennzoil Platinum full-synthetic and Castrol full-synthetic are available.

 

[keithsketchley]

I repeat that I have not advocated using anything but ATF+4, odd that people assume I have – they should look in their mirror and ask why.


I will talk to a dealer and keep trying to find actual text of Chrysler’s specifications (which are confused by their being MB specs, recall the two companies were together for a while). Meanwhile I will use Castrol TransMax ATF+4 for a while then change the pan quantity to whatever seems best at that time and the filter again.


ATF+4 exists for a reason, likely design techniques in Chrysler-designed transmissions, whereas some other manufacturers have different characteristics so have their own unique specification. Note too that automatic transmission fluid usually but not always contains “friction modifiers”, presumably because most ATs have clutches whether disk or band type and clutch engagement (now including TC lockup) and release is important to smooth shifting. (CVTs being a different beast – they operate completely on friction whether cones or belts, auto-manual clutched gearboxes I know nothing of.) And designers have invented ATF variations to compensate for marginal designs – as Ford did to mitigate shudder of the TC lockup clutch. AFAIK Chrysler didn’t do that, just improved their ATF+ spec (now on v4).


I repeat that I have not advocated using anything but ATF+4, odd that people assume I have – they should look in their mirror and ask why.


I will talk to a dealer and keep trying to find actual text of Chrysler’s specifications (which are confused by their being MB specs, recall the two companies were together for a while). Meanwhile I will use Castrol TransMax ATF+4 for a while then change the pan quantity to whatever seems best at that time and the filter again.

 

[keithsketchley]

Fluid temp affects viscosity, viscosity affects pressure of the fluid and automatic transmissions need to have precise pressures to operate properly.......

Good general info thanks.

Diesel fuel might have been the additive, has some lubricity, in its severe winter form it is essentially aviation kerosene (J-1/JetA). ("Paraffin" to Brits, not the wax sold here.)

 

[keithsketchley]

I was just going to pose a question about the additives over time.
So now they say not to use the color of the fluid as a need for service? I would think the color would indicate metal particles or clutch materials in the fluid from wear.

I remember my friend pulling the dipstick on the transmission on a 1980's vintage Ford and the trans fluid was gold. That trans was done.

Brown would be common due to deterioration of the fluid.

Particles would only colour the fluid if fine and dispersed. Best to cut the filter open.

One caution is that the colour of fluid on the dipstick of the 41TE in Caravans is not representative of fluid in the transmission, in my experience.

 

[keithsketchley]

Reread Imperial Crown's post. As long as the ATF+4 you choose meets Chrysler's specs in MS-9602 it should be fine.

Reread my posts.

 

[voiceofstl]

What could happen to a transmission if it sucks in air and runs the pump dry or clutch packs dry? What could happen to a transmission if you back flow the fluid the opposite direction it was designed to go, or exceed the pressure that it was every designed to go in any particular circuit? And don't forget, a pump is stupid, if you increase the pressure at its intake, its output will go up a corresponding amount.

This is why Chrysler/FCA put out a TSB recommending against fluid flushes in their transmissions and systems.

The Owners Manual has a service schedule in it, and has an alternate "Severe Duty" schedule for things like Taxi and Fleet Service, with a more often transmission fluid change interval.

The engineers have tested this, and they have found, if you change the fluid at the recommended interval with the recommended fluid, you will replace enough old fluid with fresh to keep the transmission operating properly and well protected. This strategy is more likely to keep the transmission running properly for the longest time, than using some flush system that forces fluid through the system in a way the transmission was never designed to handle.

Now, what people often ask, what if I buy a used mini-van that never had the trans serviced and is way, way overdue..... Yes, that's a tough one, cause arguably changing only half the fluid that's in the pan might not be enough to keep the trans protected. That's why I suggested, either do the recommended service several times in the row, with enough driving in between to well circulate the fluid through the whole system. That would catch you up on the service, and get a lot more fresh fluid into the system. Arguably, you'd be draining a good amount of new fluid with the old on the successive oil changes, and tossing some money away.

You can disconnect the cooler lines and use Low Pressure Air (like 10PSI) to force the fluid out of the cooler while draining the pan, that can get you some extra capacity of fluid change, fairly safely.

There is the amateur flush, that not many people have screwed up and didn't cause problems. Where you disconnect the return line and put it in a bucket and fill the trans at roughly the same rate the oil comes out. You have to have a helper put the trans in gear. Again, you mess up and run the pan dry, you could damage the transmission.

..Let me get this right. Instead of a full flush I should just a pan drop and filter change? Then over the next 10 or 20 thousand miles do a pan drop to drain fluid I can get out and replace with new ATF+4 2 or 3 times.????

 

[Doug D]

..Let me get this right. Instead of a full flush I should just a pan drop and filter change? Then over the next 10 or 20 thousand miles do a pan drop to drain fluid I can get out and replace with new ATF+4 2 or 3 times.????

Yep. Though you probably would only need to go about 5,000 miles.

My servicing dealer recommends the drop-the-pan method at the first service, then a flush every other service. But even that is not necessary. For most, changing the fluid/filter via the drop-the-pan method as recommended is more than sufficient even though it may only be half of the total amount in the transmission. The plan fact is you can never get all the fluid changed without doing a flush.

A closer dealer to me only offered flushes with BG products. They were real reluctant to do the drop-the-pan method. I asked "What about the filter?". "Oh, the BG stuff will clean it out." I quickly got out of there and haven't been back since.