[Bob Lincoln]

If you put the car on ramps, typically overnight about 7 out of 10 quarts can drain out. So you get a 70% fluid change. Next time you drain, 30% of the 30% that remains is old fluid, or only 9% of the fill. So with 2 changes, you can get 91% new fluid. Do a 3rd change and you get 97% new fluid.

 

[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]

Besides the ones I said I found in stores, Canadian Tire sells their own brand of ATF+4 which I would not buy unless desperate, and sells Mobil ATF+4 which is labeled as “synthetic blend” (whatever that means).

BTW, Pennzoil is from Sopus Products which is Royal Dutch Shell.

 

[Rick Anderson]

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.

ATF+4 comes up on the forums often, and often the poster asking doesn't know ATF+4 is synthetic fluid and they often ask if one of the exotic synthetic ATF's would be better than ATF+4. You said you the brand of ATF+4 you use is being discontinued, and asked if you should switch to synthetic. We understand now you meant switch to an ATF+4 that advertises its synthetic, but do you see how your first post sounded like so many other in the past.

AFA, Synthetic vs Conventional......
At least FCA in their Owner's Manual will point out if Conventional is necessary or better than synthetic, by stating conventional oil/lube only. Off hand, I can think of a few small Jeep's differentials that state to use Conventional Gear Oil only. I assume because they have friction surfaces in these differentials, most synthetic gear oils having less friction might cause the friction surfaces to operate poorly compared to the conventional gear oil, but that's a guess, perhaps there is another reason that the properties of synthetic causes a problem for this particular piece of equipment.

But for most automotive applications, I have seen very few complaints or documented drawbacks of using Synthetic. Literally, if its not one of the very documented exceptions, the only drawback to synthetic is if you're wasting money on the more expensive synthetic when the conventional would protect more than well enough.

..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.????

All I can tell you is that FCA recommends against doing transmissions flushes in the transmissions that come in their vehicles, and only recommend to dropping the pan and changing the fluid that drains from that.

I have not seen any guidance on what to do if a vehicle is greatly overdue for a transmission fluid change.

So you decide what's best for you. Logically, doing the recommended service several times in a row, would be closer to the manufacturer recommendations than doing exactly what the manufacturer recommends against doing.

And while I'm sure, if you have no problems with the current fluid, doing several fluid changes in a row over 10 to 20 thousand miles would be just fine, you don't have to spread the service over 10-20k miles, you could easily do it in a day by driving 20 miles between each fluid change.

Bob Lincon had an excellent suggestion, the trapped fluid does drip slowly, so if you left the pan off to drain the transmission overnight, you get a lot more fluid changed. You remove the cooler lines and blow them out, which empties the cooler as well, you'd get even more with each change. You could even do it every weekend to leave it drain overnight, I haven't done the math, but his numbers make sense, his method could get you 90% or better fluid.

 

[keithsketchley]

If you put the car on ramps, typically overnight about 7 out of 10 quarts can drain out. So you get a 70% fluid change. Next time you drain, 30% of the 30% that remains is old fluid, or only 9% of the fill. So with 2 changes, you can get 91% new fluid. Do a 3rd change and you get 97% new fluid.

Mmmm, given that the TC can only drain through the middle hole I'm very skeptical of your values.

I haven't seen a lot more come out letting it sit for a few hours.

It is a point that half of the total TC volume could drain into the transmission if the hole in the TC shaft leads somewhere..

 

[keithsketchley]

ATF+4 comes up on the forums often, and often the poster asking doesn't know ATF+4 is synthetic fluid and they often ask if one of the exotic synthetic ATF's would be better than ATF+4. You said you the brand of ATF+4 you use is being discontinued, and asked if you should switch to synthetic. We understand now you meant switch to an ATF+4 that advertises its synthetic, but do you see how your first post sounded like so many other in the past.

AFA, Synthetic vs Conventional......
At least FCA in their Owner's Manual will point out if Conventional is necessary or better than synthetic, by stating conventional oil/lube only. Off hand, I can think of a few small Jeep's differentials that state to use Conventional Gear Oil only. I assume because they have friction surfaces in these differentials, most synthetic gear oils having less friction might cause the friction surfaces to operate poorly compared to the conventional gear oil, but that's a guess, perhaps there is another reason that the properties of synthetic causes a problem for this particular piece of equipment.

But for most automotive applications, I have seen very few complaints or documented drawbacks of using Synthetic. Literally, if its not one of the very documented exceptions, the only drawback to synthetic is if you're wasting money on the more expensive synthetic when the conventional would protect more than well enough.

All I can tell you is that FCA recommends against doing transmissions flushes in the transmissions that come in their vehicles, and only recommend to dropping the pan and changing the fluid that drains from that.

I have not seen any guidance on what to do if a vehicle is greatly overdue for a transmission fluid change.

So you decide what's best for you. Logically, doing the recommended service several times in a row, would be closer to the manufacturer recommendations than doing exactly what the manufacturer recommends against doing.

And while I'm sure, if you have no problems with the current fluid, doing several fluid changes in a row over 10 to 20 thousand miles would be just fine, you don't have to spread the service over 10-20k miles, you could easily do it in a day by driving 20 miles between each fluid change.

Bob Lincon had an excellent suggestion, the trapped fluid does drip slowly, so if you left the pan off to drain the transmission overnight, you get a lot more fluid changed. You remove the cooler lines and blow them out, which empties the cooler as well, you'd get even more with each change. You could even do it every weekend to leave it drain overnight, I haven't done the math, but his numbers make sense, his method could get you 90% or better fluid.

 

[keithsketchley]

SAE Paper 982674 on development of the ATF+4 specification advised that the Group III “base oils” are usually made from petroleum because that was at the time a lower cost approach. (Two decades ago.) It also illustrates the many process steps to get a good product, which I take in general to add cost. It illustrates some of the criteria, including performance at low temperatures.



A web page says a base III oil can be either or synthetic.



(One characteristic of synthetic motor oil is more uniform molecule size, but I don’t know how significant that is. My understanding is that synthetic motor oil is made from natural gas, Shell has had a plant in SE Asia for over a decade, and was planning to build one in the Middle East.



Beware that the term “synthetic” is used rather broadly by some people. Products like the base oils used in ATF are the result of much processing, they are a long way from crude oil. I take “synthetic” from engine oil which is often made from natural gas. I note again that Pennzoil in the silver bottle is labelled “full synthetic”. Some people use the term synthetic for fluids made by chemical means rather than the distillation common in refining. Noria’s web site lists hydrocracking as the method of making Group III base oils, I think that’s distillation using even higher pressure and temperature and catalysts (see PetroCanada’s Specialty Base Oils and Fluids brochure which says Group III base oils almost match Group IV synthetics), whereas Group IV and V are synthetics.



And the term “base oil” is fairly broad, but Chrysler’s testing was specific. The CCC-Group lists several versions and notes which are best for ATF. People have used the term “blended” for ATF+4, which is not surprising but we’d have to get specific as the elixer is a blend of various things (base oil plus friction modifiers, for example).

 

[keithsketchley]

LubeGard’s web site has a graph showing lockup with torque of various fluids. (In developing a spec for ATF+4 Chrysler used a LubeGard product in a Group III base oil.)



An article The History of ATF – 2006, by an oil specialist James Dickey, is useful for identifying some of the factors in ATF including why Ford avoided “friction modifiers” for years, how better low temperature performance was achieved, and mucking around to improve fuel economy.



http://motoroilbible.com/blog/group-iii-basestock-quality/discusses Group III base stocks, opining that each variation in use should be tested against the end product specification. (People herein have talked about ATFs that claim to meet Chrysler’s spec but have not been approved by Chrysler’s QA agent.)



Note a thread in the Moparchat forum saying the Chrysler TSB that introduced ATF+4 says to continue using ATF+3 in 1999 and earlier vehicles to reduce TC shudder “on breakin”. (Dunno what that means as those vehicles would already be broken in, except in case of a rebuilt transmission.)

 

[keithsketchley]

I am wary of manufacturer claims of backward compatibility as they may not be well-researched.
For example, an IBM battery listing for a computer was corrupted when a fancier model was introduced, some fool changed the listing for the original design to the battery for the new design which is physically different to accommodate a display pivot hinge.
And Microsoft botched in Office 97, changing the .doc format to RTF and using a newer version of RTF – that fouled up WordPerfect’s reading of .doc files, so Microsoft had to patch its software.


Note a thread in the Moparchat forum saying the Chrysler TSB that introduced ATF+4 says to continue using ATF+3 in 1999 and earlier vehicles to reduce TC shudder “on breakin”. (Dunno what that means as those vehicles would already be broken in, except in case of a rebuilt transmission. May not be a big problem.) I haven't found the TSB yet, the link in that forum is not valid.

 

[Rick Anderson]

SAE Paper 982674 on development of the ATF+4 specification advised that the Group III “base oils” are usually made from petroleum because that was at the time a lower cost approach. (Two decades ago.) It also illustrates the many process steps to get a good product, which I take in general to add cost. It illustrates some of the criteria, including performance at low temperatures.

A web page says a base III oil can be either or synthetic.

(One characteristic of synthetic motor oil is more uniform molecule size, but I don’t know how significant that is. My understanding is that synthetic motor oil is made from natural gas, Shell has had a plant in SE Asia for over a decade, and was planning to build one in the Middle East.

Beware that the term “synthetic” is used rather broadly by some people. Products like the base oils used in ATF are the result of much processing, they are a long way from crude oil. I take “synthetic” from engine oil which is often made from natural gas. I note again that Pennzoil in the silver bottle is labelled “full synthetic”. Some people use the term synthetic for fluids made by chemical means rather than the distillation common in refining. Noria’s web site lists hydrocracking as the method of making Group III base oils, I think that’s distillation using even higher pressure and temperature and catalysts (see PetroCanada’s Specialty Base Oils and Fluids brochure which says Group III base oils almost match Group IV synthetics), whereas Group IV and V are synthetics.

And the term “base oil” is fairly broad, but Chrysler’s testing was specific. The CCC-Group lists several versions and notes which are best for ATF. People have used the term “blended” for ATF+4, which is not surprising but we’d have to get specific as the elixer is a blend of various things (base oil plus friction modifiers, for example).

As I understand it, Group III oil includes a "Hydrocracking" process, among others, but what they do over just refining oil to get a range of molecule sizes, the hydrocracking then breaks the molecule chains to get them to the desired length.

As I understand it, Group IV oil is manufactured starting with pure gases combined in process's to form the engineered molecule. Are some of those gases natural gas, or natural gas synthesized to form a more pure gas to use as the Group IV building block, I don't know.

I spoke earlier about the lawsuite brought against Castroil for using Group III oil and labeling it synthetic. The court decided Synthetic was "Marketing" Term, and as long as the oil went through any kind of synthesizing process, which "Hydrocracking" is, it could be called Synthetic.

Group III oil manufacturing may not be cheap, but its cheaper than Group IV manufacturing. That is why its believed most of the store shelf brands have switched to Group III oil in their Synthetic labeled products, and this was years ago, and while the price went up on a lot of oil products it didn't as much for these synthetics. It's believed the Exotic Brands of Synthetic Oil are the only ones offering Group IV oil, AMSOIL, RedLine, Royal Purple, etc....

LubeGard’s web site has a graph showing lockup with torque of various fluids. (In developing a spec for ATF+4 Chrysler used a LubeGard product in a Group III base oil.)

An article The History of ATF – 2006, by an oil specialist James Dickey, is useful for identifying some of the factors in ATF including why Ford avoided “friction modifiers” for years, how better low temperature performance was achieved, and mucking around to improve fuel economy.

http://motoroilbible.com/blog/group-iii-basestock-quality/discusses Group III base stocks, opining that each variation in use should be tested against the end product specification. (People herein have talked about ATFs that claim to meet Chrysler’s spec but have not been approved by Chrysler’s QA agent.)

Note a thread in the Moparchat forum saying the Chrysler TSB that introduced ATF+4 says to continue using ATF+3 in 1999 and earlier vehicles to reduce TC shudder “on breakin”. (Dunno what that means as those vehicles would already be broken in, except in case of a rebuilt transmission.)

I spoke about ATF+4 having a superior additive package that was more durable than any other additive package, that might be the LubeGuard reference you're quoting.

I forget if it was in the TSB or a write up here on allpar explaining the logic on the TSB, but they did find ATF+4 could cause TC lock up on older transmissions that weren't broken in, because they used a previous friction material not in use on the newer transmissions. Once broken in, the TC lock up wouldn't shudder. Thing was, there were still rebuild kits on the shelves that would be used to rebuild transmissions in service, and thus newly rebuilt transmissions that used ATF+4 could experience the shudder. That why they didn't recommend retro-fit with ATF+4 right away for those earlier transmissions. After a year or two, when they were confident all the kits with previous friction material had been used up and transmissions were only being rebuilt with the new friction material, and any trans with the old friction material had been broken in, they issued a revised TSB recommending ATF+4 for retrofit in all transmissions.

 

[Stratuscaster]

I cannot recall where I saw/read it, but there was an article/post/something where an individual disconnected the trans fluid lines at the trans cooler, placed the "output" line in an empty bucket, and placed the "input" line into a large bucket filled with fresh ATF. Fired up the car and essentially allowed the fluid to "change itself". When the fluid coming out appeared to be the same as that going in, he turned the car off, reconnected the lines, checked the level and topped off as needed.

I do not recall what model/make this vehicle was, and I've not tried this method myself - I've instead done the "change twice" method on my own cars.

 

[Rick Anderson]

I am wary of manufacturer claims of backward compatibility as they may not be well-researched.
For example, an IBM battery listing for a computer was corrupted when a fancier model was introduced, some fool changed the listing for the original design to the battery for the new design which is physically different to accommodate a display pivot hinge.
And Microsoft botched in Office 97, changing the .doc format to RTF and using a newer version of RTF – that fouled up WordPerfect’s reading of .doc files, so Microsoft had to patch its software.


Note a thread in the Moparchat forum saying the Chrysler TSB that introduced ATF+4 says to continue using ATF+3 in 1999 and earlier vehicles to reduce TC shudder “on breakin”. (Dunno what that means as those vehicles would already be broken in, except in case of a rebuilt transmission. May not be a big problem.) I haven't found the TSB yet, the link in that forum is not valid.

I've really lost as to what point you're trying to make now? What does PC batteries have to do with synthetic oil?

If you really believe that switching to synthetic oil could have drastic undocumented drawbacks, then simply don't do it.

If a product is labeled "ATF+4" as in, the big label claiming it is ATF+4, then they have been licensed by FCA itself as being blended and meeting FCA specs ATF+4. You should not encounter any problem using it. Yes, there are more than few ATF's that in the fine print on the back of the bottle claim they can be substituted for ATF+4, they are documented on FCA's ATF+4 license webpage, there was a link on one of the first posts. Don't use one of those unlicensed ATF's claiming to be able to substitute for ATF+4.

Could different brands of ATF+4 have different blends of Group III or Group IV oils or even some conventional oil as well? I don't know. But if they got licensed by FCA to label it ATF+4, then FCA is certifying that they have met the specs. So either they are all the same in the blend of the base stock or the ones that differ FCA still approved it as meeting their specs and protecting the transmission adequately.

The retro-fit of ATF+4, I explained in the previous post, it was a deal of rebuild kits at the time having old materials that would shudder with ATF+4, a couple years later after all the kits using the old material had been used up and those rebuilt transmissions were all broken in, they revised the TSB to recommend ATF+4 for all previous Chrysler Transmissions. If they are explaining the reasoning in that detail, it sounds like to me, they have done their research.

 

[Rick Anderson]

I cannot recall where I saw/read it, but there was an article/post/something where an individual disconnected the trans fluid lines at the trans cooler, placed the "output" line in an empty bucket, and placed the "input" line into a large bucket filled with fresh ATF. Fired up the car and essentially allowed the fluid to "change itself". When the fluid coming out appeared to be the same as that going in, he turned the car off, reconnected the lines, checked the level and topped off as needed.

I do not recall what model/make this vehicle was, and I've not tried this method myself - I've instead done the "change twice" method on my own cars.

I've done this in my Grand Caravan and other vehicles. I have not encountered any problems. But it is possible you could screw up and suck air into the transmissions inner working and possibly cause damage.

You will need to have a helper shift into Reverse and Drive and Low. At idles with a cold transmission, the flow will be so slow it would take forever. As well, if your intent is flow all the old fluid out and new fluid in, then you would need to engage each circuit in the transmissions, not just one.

Most of the later transmissions will have some form of thermostat that will redirect flow back into the transmission. So this method is far from perfect also, the old and new fluid would be getting pretty well mixed as you pump it out. But, I found you could notice a difference in color in the fluid at least indicating to me, it was mostly old being forced out until all out and mostly new then coming out.

Remember, most of the professional flushes have machines forcing fluid into, some in the opposite direction to back flow. As I understand it, this is the reason why some flushes have damaged transmissions and why Chryslers engineers looked at it and decided to recommend against it, as being to likely to cause transmission damage, since the transmission was never designed to be serviced like this.

Now the amateur flush, doesn't do the pumping and pressures into the transmissions, you're simply catching the fluid be directed to back to the transmission pan. Like I said there are still risks with doing this, you could screw up and damage your trans, but if you do it right, logically it shouldn't hurt the trans, even if its not recommended. (and its probably not recommended simply cause the engineers know DIY'er will screw it up).

 

[Stratuscaster]

Noted. The article made sure to note that the "new" bucket contained more than the capacity of the system in an attempt to avoid the "sucking air" scenario.

Back to "what ATF+4 fluids are licensed" - Licensed Brands | Chrysler ATF+4® Licensing Program
I've used the "SuperTech ATF+4" from Wal-mart without issue in several Chrysler FWD vehicles. It tends to be the least expensive and is readily available, as every WM store in a 10-mile radius of my home stocks it.

 

[ImperialCrown]

This is close to the principle used by the ATF flush 'transfusion' machines used in shops. A two-chamber rubber bladder, one side expanded as filled with fresh ATF, then connected to the cooler inlet hose. The empty bladder side is connected to the cooler outlet hose. The engine is started, sometimes the car is placed in Neutral with the parking brake on to begin circulation.
As the empty bladder fills with old fluid pushed out of the transmission, it pushes against the bladder with the fresh fluid and pushes it into the transmission.

 

[Doug D]

If you really believe that switching to synthetic oil could have drastic undocumented drawbacks, then simply don't do it.

If I understand the OP's original concerns, his understanding is the ATF+4 he was using (gold bottle Pennzoil ATF+4) is not a true synthetic (made from Group III stocks) and the new silver bottle Pennzoil is made from Group IV stock (pure synthetic) and since the A604/41TE he has was not designed with pure synthetics in mind, it will possibly hurt his transmission. Therefore he is/was looking for a suitable replacement.

The reality is what he think is not quite correct. So long as a fluid (group III or group IV) meets the specs outlined in MS-9602 it is correct for the vehicle. As far as the market is concerned they are both synthetics and are backwards compatible for vehicles that previously used ATF+3 such as the '93 and '94 vehicles he has.

 

[Rick Anderson]

If I understand the OP's original concerns, his understanding is the ATF+4 he was using (gold bottle Pennzoil ATF+4) is not a true synthetic (made from Group III stocks) and the new silver bottle Pennzoil is made from Group IV stock (pure synthetic) and since the A604/41TE he has was not designed with pure synthetics in mind, it will possibly hurt his transmission. Therefore he is/was looking for a suitable replacement.

The reality is what he think is not quite correct. So long as a fluid (group III or group IV) meets the specs outlined in MS-9602 it is correct for the vehicle. As far as the market is concerned they are both synthetics and are backwards compatible for vehicles that previously used ATF+3 such as the '93 and '94 vehicles he has.

Yea I'm starting to see that is his concern. He seems to think switching from conventional to synthetic or Group III to Group IV synthetic, could have some drastic repercussions.

My experience has confirmed the conventional wisdom on synthetic oil for automotive applications. Unless the Owner Manuals specifically recommends Conventional Oil only, then Synthetic is an option and in most cases it will provide superior performance. Its really an argument of if the extra performance is worth the cost. There are a few cases where the properties of synthetic don't match the equipment and they are rare, but in those cases the owner's manual will warn you.

I've rarely heard that and in cases where they have switched back to conventional from synthetic, wasn't because it drastic problems, merely the conventional was slightly better for the circumstances of a particular application. E.g. the large TurboFan motors in one airline, which surprises me since synthetic oil was developed to address the problems gas turbine engines had with conventional oil. But decades later with improved designs, its possible these particular Hi-Bypass Turbofans run cooler than past gas turbine engines but have a problem with oil leaking pass the seals (all gas turbines do), and in this one application the greater coking of synthetic and the lesser need for heat resistance, resulted in conventional oil being a better solution. Lets keep in mind, the airlines are a business that they try to save every penny, and the coking might have been less of serious problem and more of a save money by reducing the maintenance to remove the coking.

As well, I suspect Penzoil is taking advantage of FCA finally advertising ATF+4 is synthetic, in the past they never made any mention of it. So Penzoil very well may not be making a single change to their ATF+4, they are simply rebranding it as one of the Synthetic products, which is was synthetic all along, they just had it grouped in their conventional products like all the other manufacturers do with their ATF+4.

Regardless, ATF+4 is licensed by FCA, if its ATF+4 on the big label on the front of the bottle its licensed to meet the specs and will work like intended. If Penzoil changed something in their ATF+4 to rebrand it as part of their Synthetic Family of products, if it still has the ATF+4 label, then Chrysler certified it will work like intended.

BTW, some of the popular synthetic motor oils do NOT meet the Chrysler spec for motor oil. That is because FCA has a ridiculous spec that takes a long time to pass. There is no reasons to suspect those synthetics would have any problem passing the spec, but because they make the spec such a lengthy and complicated process some of them simply don't bother. Mobil1 is one of them, many, including myself, use Mobil1 Synthetic Motor Oil in their engines and never have encountered any problems with an engine that lasted into very high miles.

 

[Doug D]

Regarding the synthetic vs conventional debate when it comes to motor oil for the engine, I've always used conventional. I don't debate that synthetic (whether it be from group III or IV) is superior in many respects to conventional motor oil. For me conventional motor oil has always met the requirements of my vehicles so long as I used the recommended viscosity. I've had several vehicles log well over 200,000 miles (one over 300,000). Plus today's conventional oils are far better than the conventional oil from just 5 years ago.

 

[Rick Anderson]

And much better than conventional oil of 10 and especially 20 years ago.

Like I said, the biggest argument against synthetic motor oil is it worth the cost. In most cases of typical usage and conditions for an automobile, conventional oil is going to protect and perform more than adequately.

 

[pt006]

Bob L; In my experience, after 2 weeks up on ramps a 41-TE 4 speed was still dripping. The bottom half of a torque converter will never drain. Not sure about the cooler. I've thought about removing the tranny filter and making an adapter to fit into the suction hole, connect a heater hose to it, then stick the other end of the hose in 5 gallon bucket of ATF. Then catch the old fluid in a BIG pan. Start and run the car thru the gears. Not sure if this would flush the cooler though.