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I did it!
A Jatco ATF (automatic transmission fluid) complete full flush (transmission fluid change) on a X400 X-Type Jaguar.
I would like to think that this thread and "invention of a new procedure" is one of my masterpieces in this forum so far...
Today it was too hot to go outside, thus I typed this DIY Guide up...
This is for X400, X-Type, Jatco jf506e transmission, as found e.g. in the 2.1L FWD X-Type and 2.5L AWD X-Type (Note: Some X-Type have other transmissions).
Mine specifically is a 2006 FWD 2.1L X-Type with the Jatco JF5006E transmission.
Standard procedure for the ATF change on a jf506e transmission is to drain a bit (the little something, which drains voluntarily), refill (the same small amount), drive (to mix old and new ATF), drain, refill, drive, drain, refill. This it then considered generally to have been a complete ATF change.
Lacking better information I had to do exactly that on my X-Type about 2-3 years ago. And I had an additional handicap: The CORRECT ATF for that transmission is not available in Australia. Plus, that was back at a time, when I was naïve enough to trust that what Multi-vehicle ATF manufacturers write on the products is the truth, naively thinking that surely there would be consumer-protection-agencies making sure that they do not write bollocks regarding the suitability of their ATF. Well: Wrong!
It was only last year, when I wrote my DIY guide regarding ATF full flush on the S-Type in this forum, when I was told (mainly by Don) to be very carefully about those fake multi-vehicle ATF claims. As I am "teachable" I dumped the just filled synthetic multi-vehicle ATF again, as it was very obviously utterly unsuitable for the S-Type and I bought ZF Lifeguard 6 instead for the ZF 6hp26 transmission. I did the S-Type full flush there by unscrewing the UPPER pipe on the radiator coming FROM the transmission to purge the old ATF bit by bit by first draining the old ATF, changing the filter, and refilling - that newly refilled fluid is then being pumped thru the system effectively throwing out the old ATF via that just mentioned removed pipe. With bit by bit I meant that you have to stop doing that many times, always refilling the ATF. Doing that until you are confident that what comes out looks clean. Then reconnect the pipe and bring the ATF to the correct level.
I am writing all this, as the whole thing was a learning process of how I figured out of how to do the X-Type full flush - and it goes on...:
Cause next in line was the ATF full flush on my X308 (Jag XJ8 1998). Yes, I could have done it just like on the S-Type, with the exception that you have to know that the pipe on the radiator coming FROM the transmission is now the LOWER pipe, else it gets very messy! But I felt creative and in the mood to try something completely different (just like Monty Python... ). Plus, it was very tempting to try that, as I had BOTH pipes, which connect to the transmission, removed from the radiator anyway, as I had the whole radiator removed to be able to replace the timing chains.
But before I continue, here my usual disclaimer: I am not to be held responsible, if my post creates ideas, which then result in injury and/or damage.
This is very important here, as I am doing something, which worked for me, but I cannot guarantee at all, that this new method, which I have not seen or heard of anywhere else, would not do damage to the transmission...
So with that introductory foreword, I was thinking of how I can do an ATF full flush on the Jatco JF506E.
I could not find any hint on the net - just that old drain a bit, refill at bit and drive a bit times 3.
I also asked that question here in the forum, but if did not look like anyone had ever done a full flush: https://www.jaguarforums.com/forum/x...x-type-266112/
And as mentioned above, I had lost every bit of confidence in the multi vehicle ATF, I filled in there 2-3 years ago. So mixing that stuff with a good and hopefully suitable ATF was not an option...: So how can I do a full drain of the whole approx. 8 Liters of ATF? That was the challenge.
WHICH ATF?:
Briefly a word about the ATF for the Jatco jf506e: Recommended are Idemitsu K17 (which seems to be called Idemitsu Type J these days) and Ravenol jf506e.
Both are not available for sale in Australia. So got for them, if you are in a country, where you can get them.
Also: That Jatco is being used in many brands of cars, and every brand sells Idemitsu K17 under their own brand-name, but still: Not available in Australia.
Thus, after extensive research I had a good hunch and a good feeling regarding ATF Fuchs Titan 4400.
I found a good source for this in Australia.
For the S-Type I needed 14L of ATF, for the X308 (with the new air pressure method only 11L). As I have two X-Type (2.1L FWD and 2.5L AWD, same jf506e, luckily), I thought that 10L ATF for one X-Type would not suffice, especially, if I would have to do the drain, refill, drive thing 3 times in the end anyway. So - since I picked the ATF up myself about 120km away to save the postage cost - I bought 2 x 20L ATF. Spoiler alert: As it turns out, that this is enough for fife jf506e full flushes!
New method:
Thus, with both pipes being accessible, I CAREFULLY - with the ATF release plug removed - blew compressed air into both pipes. This, in combination with letting the ATF drip out over some nights before and at least one night afterwards, removed the complete ATF contents from that ZF 5hp24 transmission, so that the above described procedure (as I did it on the S-Type) was not required anymore. And I refilled the 5hp24 with one the of the few suitable ATFs for this kind of transmission, which is Esso or Mobil LT71141 (same thing, as Esso and Mobil is now the same company).
Note: I could not have been 100% sure that this "blowing of air into those pipes" would not damage anything. I still cannot be sure, but it worked for me and I made sure that in case of over-pressure the excess pressure could still come back out at the point where I held the air-pressure-gun by not pressing the air-pressure-gun onto those pipes too tightly.
THUS, how to translate the knowledge of how to do a full flush on the S-Type and X308 (two methods) over to the X-Type Jatco jf506e transmission?
What I gather from various you tube guides and threads regarding the X-Type ATF change procedure, each drain delivers about 3.25 - 3.5 quarts of old ATF in the drain-pan... That is a mere 3 - 3.3L with about 8L being in the transmission, that is really not a lot at all.
I know that one really should not run a car with the ATF being drained. That said:
1. I did exactly that accidentally once on the X-Type a few hours or even a day after the 3.5 quart drain - no damage done luckily..
2. I reckon it makes a difference, if you drain the ATF, and let the car standing there for 1 or more days, so that the transmission is really dry inside and start
the car then. That could be real bad. Again, better another warning: Don't try this at home! I did the following, no damage to the X-Type transmission, but
that is not a guarantee...:
PROCEDURE in detail:
1. Let the engine run for a while to get to 30-40°C. That is not long at all in Australia! I used the time to switch thru the gears (FOOT ON BRAKE!). The car
was already jacked up in a level position.
2. I opened the ATF fluid level check bolt under the car with then engine running (cause that ishow your check the ATF level: WITHTHE ENGINE RUNNING!
See pictures below of where to find that check level bolt! Never open that funny bolt accessible from behind the wheel housing on the side - thinking
mistakenly that you find an ATF-level-check-bolt there: It is very likely that you accidentlly remove THAT bolt, which, if removed, would KILL YOUR
REVERSE GEAR!). A wee bit of ATF came running out.
3. Then - and that is the hairy bit: I opened the size 24 ATF release bolt (with drain pan underneath) WHILE the engine was running.
Obviously I loosened that bolt a wee bit before, so that I know it would open, when I want it to. But mind you that I switched off the engine roughly 8 seconds after I opened the drain-bolt! (The driver side door was open so that I could quickly get to
the key (opening the window beforehand is another option.)
The idea of doing this came to me as a result of the ATF drain, which I did on the S-Type: The transmission fluid pump runs while the engine is running! I just
wanted to make use of that the best I could (so this was a lesson leaned translated into something new...).
The success was tremendous: While the normal drain procedure seems to give you a wee bit more than 3L, I had removed now ALREADY the first 5.5L!
PS: Those 5.5L included the amount, which continued to drip out during the night to follow that drain...
Thus, less trouble for later...
4. And next came what I learned from by X308 ATF change: The air-pressure-gun method.
And in pictures this looks like that:
The whole sage starts with jacking up the X-Type level and removing those 3 plastic shields shown above (the that x-bar - more about that later).
This is the above mentioned ATF level check bolt. Properly hidden behind that little bracket held by just 2 little bolts. While you don't have to, I removed that bracket to get better access to the check-bolt and to be able to see properly, how much flows out of there, when opened.
Those are the the 2 pipes connecting the transmission to the radiator. They are both pretty low down there on the radiator. Actually, there are not accessible with the x-bar still in position (the function of which is to hold the radiator and the plastic shield up). It's a bit of a bother to remove those 8 bolds, which are holding that bar in position. Way too many bolts actually - they could have don't without the badly accessible ones (1 on each side). Note the 4 bricks: With the car jacked up to the right level, those 4 bricks hold up the radiator after removal of the x-bar.
That's the x-bar lowered already. After complete removal of that x-bar, there is proper access to those 2 pipes.
SPECIAL TOOL: That is actually the cheapest special tool I can think off. I bought a whole box (different sizes) of them on Aliexpress for A$4.40. It's called "7pcs Pipe Disconnect Fuel Line Disconnect". It's required to swap the S-Type fuel filter, the S-Type fuel lines in the engine bay and the same in the X308, the fuel lines connecting to the fuel rail. X-Type fuel pipe as well and obviously those 2 pipes. You fiddle it in position and then turn it 45° so that it hold up all 4 clips at the same time. Then, by moving the pipe forward and backward, you can pull the pipe off.
Have a second fluid waste pan ready under those pipes. (the first one is under the release plug). Just to be 110% sure: I marked the lower pipe with a pink line so that I would not mix them up later.
The upper pipe can be removed the same way. I placed a tiny bit of PVC tube over the air-pressure-gun to increase its outer diameter a bit. HERE I clean out the excess ATF from the radiator by blowing into the upper one of the 2 little radiator flanges. I don't think anything could happen there... It's a little bit messy, but shown in the next picture is the improved method:
I connected a dedicated "waste-pipe" to the lower flange.
With the ATF reservoir in the radiator emptied, now for the big fun: Getting the remaining ATF out of the transmission. With the drain plug open I applied air-pressure with an air-pressure-gun via those hoses. I made sure never to forcefully press the air-pressure-gun into those pipes - just to avoid a potential damaging build-up of over-pressure somewhere in the system. I permanently swapped the pipe, hwere to apply air-pressure. The ATF came out by the drain-plug-hole (more so when blowing into one pipe rather than the other, and especially the also came out quite a bit of ATF from one of those pipes after applying air-pressure. After all that I let it sit and drip over night and applied again air-pressure on the next day. By doing all that I managed to get another 2.4L on top of the already removed 5.5L out of the system. That is 7.9L in total!!!
So again: air pressure into both pipes...
The first picture of this thread showed already the freshly repainted x-bar...: While it is a bit of work to remove it to get access to the pipes, it is a very good idea anyway, because it was very very badly rusted. And here in Australia cars really do not rust easily, thus, I don't even want to know, how those x-bars look in countries with snow and salt on the roads... The process from right to left: rusty, magic with wire brush on angle grinder (wear eye protection!), and painted with black Zinc paint and then clear coat. The x-bar is light weight, i.e. this metal, i.e. it would rust thru easily... So even if you do not want to change your ATF, maybe better repaint that x-bar... Note the neat trick to hang the freshly painted x-bar up for drying on the cloth line (on a Hill's Hoist - or to be historically correct: A Gilbert Toyne Aeroplane Cloth Hoist, an idea stolen by Lance Hill).
Pipes both stuck back on, x-bar refitted, bricks removed. Ready for refill:
Using a fluid transfer pump I pumped a few ml more than 8L into the transmission via the removed filler plug left of the battery. You may wonder, how I could possibly know, how much I pumped in there with that setup...: I checked the MSDS of that specific ATF: The density is 0.85g/cm3. Plus, I have a scale... Thus: 0.85kg/L. 20L=17kg (total weight with canister was 18.2kg. 8L=6.8kg. Thus, before I started: canister=18.2, with 8L removed, canister=11.4kg. Three times after starting the refill I put the canister back on the scale. The third time it was 11.3kg. Thus, I pumped 6.9kg in, i.e. a wee bit more than 8L.
My setup to fill the ATF without having to remove the battery - would not have been a bit deal, but why, if not required...
This is my "resting position" (to avoid spillage) of the tubes of the transfer pump, while I go and check the weight of the canister. Thus, when EVERYTHING was done, I wanted to go about very careful starting the car, as I thought it might potentially be an issue that the ATF is NOT YET in every corner of the transmission, where it is supposed to be. So I started the engine and immediately switched it off again. The idea was to build up a tiny bit of ATF-pressure via the ATF pump, and the idea was to initially go thru the gears with the engine switched off. So engine on and off. All good. Foot on brake, going thru the J-gate...: Mhhhh, not good at all. It felt like nothing, when I moved thru there, also the selected gear always lights up: Lit up was - since I left "P" - he "R", regardless of where I moved the selector in the J-gate to. Not good. But I did not panic! (First rule of the Hitchhiker's guide to the Galaxy: 1. Always carry a towel! Second rule: 2. Don't panic! ). The display in the X-Type telling me "Gearbox fault" and the fact, that the car could no longer be started at all, and that I could not go back to "P" at all, did not help... - but: Don't panic! Thus, thinking logically, like Spock, from there: Of course I cannot start the car: I can't to back to "P", and if I go to "N", I am for some reason not really in "N", but in "R", as that is, which is lit up: "R". And I cannot start in "R". This warranted another look under the car:
"Blistering barnacles!", I forgot to screw that little bracket back on, the one with the two little bolts covering the ATF-level-check-bolt! And this is not just another protective bracket like the one next to it (the one on the very last picture of this thread), but this bracket ALSO holds the cable between the J-gate-selector and the gear selector under the transmission in place... As it turned out, it had quite a bit of a disasterous effect, forgetting that: Without that bracket being attached, the cable dislodged somehow from the gear selector in the car, so that moving it thru the J-gate had no effect at all. So I removed that just mentioned protective cover, and saw what is shown in the picture above: The gear selector under the car, under the transmission. There I could move the lever to the front, and thereby selecting the "lost" "P" position again. "P" was then lit up on the J-gate, and I could start the car again (foot on brake always - just in case!). However, moving the J-gate-selector had no effect whatsoever... So I became very relieved at that point, as it became now very obvious that the transmission should be fine, and I am dealing with a mere simple mechanical issue related to the cable only... - something a bicycle-repairman can do...
So I disassembled the gear selector assy in the car (starting by pulling up the "wooden" bezel from the front). Then removing the 4 smaller torx bolts. This allowed me to wiggle the culprit, the cable-connector-"pin", back into position. Small pic left: dislodged / small pic right: reconnected.
And as you might know already: Whenever I remove a rusty part anyway, it is not rusty anymore, when I put it back...
No more fault displayed on the display, no failure readout via diagnostic, everything works.
So again: Eureka!
Maybe this was the first real FULL FLUSH on a Jatco JF506E in history...
Additional note:
When doing this air-pressure removal of the complete contents of the old ATF, I found also a few very tiny metal particles in the removed ATF. Obviously, every little bit of particle being removed from the system is a huge win....
Obviously, as a last step: CHECK ATF LEVEL! :
With the engine running, as this is when you check the level:
With the temperature of the ATF between 30 and 40°C, and after having gone thru all the gears on the J-Gate (WITH THE FOOT ALWYAS ON THE BRAKE!), while waiting for a few seconds in every gear position, I put the car in "P" and removed the ATF-level-check-bolt. I made sure NOT to remove that bracket around it this time, BECAUSE - obviously, after that lesson just learned: There would be a chance that if you remove the bracket and the car is running, while you are sitting in front of it to check the ATF-level, that that car could suddenly drive over you or drive away from you - both are two non-favorable scenarios. That is my FMEA made!
Well, I had ATF coming out, a bit more than a dribble, put not a strong stream. I decided to close the check-bolt again thinking better a few drops more then too little, cause who knows, how "perfect - or not - my leveling attempt of the car had been...
AND NOW FOR THE VERY BEST OF IT ALL:
I drove the 2.1L X-Type after this FULL ATF CHANGE...
I could hardly believe it: It just sped off like mad!
I say, this 2.1L FWD only X-Type accelerates now like a 2.5L AWD X-Type!
Since I removed just a wee bit less than 8L of ATF and refilled just a wee bit than 8L, this difference in performance before and after ATF change just cannot be due to a higher ATF level (meaning it would have been to low before, which it was not). It just has to be the quality/suitability of the ATF. I mention at the top, that I mainly did this ATF change, because I lost all trust in the ATF, which I put in there 2-3 years ago - well rightfully though!
I think what was happening before, was that the 2 "discs" in the torque converter could not "connect/synchronize" properly, as that multi-vehicle ATF just was not up for the job, while the new Fuchs-ATF is....
And I am not imagining: I asked my wife to tell me what she thinks - she thought exactly the same after driving it.
PS: Unrelated and related at the some time...:
I wanted to make best use of the just drained ATF...: I have a fairly new replacement transmission Jatco JF506E sitting in my garage (just in case I would not be able to fix the transmission of my 2.5L AWD (I bought it without reverse gear)). So I just wanted to poor that surplus ATF into the transmission sitting there, which I did, but there was so much stuff around it that I did not notice that I was flooding the garage with ATF... Initially I suspected the 2 pipes, but no, their outflow is mounted too high up on the transmission... - then I got it: The drive shaft is not installed, and that's where it came out. I actually have an old drive shaft, as I swapped them on my 2.1L X-Type (I had a vibration problem, and that solved it). I'll try to get the rust off on that, stuff the opening with it, and finally fill the ATF into the stored transmission to avoid corrosion over time.
PLEASE ALSO CHECK MY ADDITION AT THE LINK BELOW - ANOTHER IMPROVED WAY FOR A "THOROUGH" ATF CHANGE DONE ON ANOTHER X-TYPE:
Excellent DYI instructions, with pics ! Thank You Peter_of_Australia and greetings form up north (Finland, -5 deg. C at the time writing this..)
Having just done timing chains replacement to my 2004 2.5 AWD (without removing the engine from the car), this is going to be my next oily job.
Thanks, Mp-X,
I have already installed a new drive belt on my 2.1L X-Type - and realized that it was not the driving belt, which was squeeking all along - it was 2 buggered idler pulley-bearings... the X-Type engine is installed 90 degree twisted, ie the belt is on the right side rather than being at the front and is rather difficult to access. But this means, that the timing chains are also not at the front, but on the right... So you would have had your fun doing the timing chain swap without removing the engine... And I only just swapped the timing chains on my X308 (I removed the main radiator, but not the A/C radiator and not the engine).
Tough choice: +35°C or -5°C... ...better increase the coolant-concentrate/water ratio in your radiator...
The simple way (and standard practice) for a full flush is to disconnect a line at the cooler let the trans pump out the old fluid, while you keep filling the pan with new fluid.
Hi Michael Davis,
I am fully aware of the method you are talking about, and I did it that way on the ZF 6hp26 (S-Type 2004/2005) and on the ZF 5hp24 (X308) and I posted those DIY guide in the S-Type section and in the X308 section.
I did those ATF full flushes before I did it on the X-Type's Jatco jf506e.
I asked around, if someone knows, how to do a full flush there - but no.
Your videos above are in regards of transmissions, which are similar to ZF 6hp26 and 5hp24.
The videos are not about X-Type or Jatco jf506e.
I think that the Jatco jf506e is a different kind of kettle...
I just cannot be sure if basically the "computer data storage principle" FIFO is applicable for the jf506e.
FIFO = First in, first out, and by that I mean: Firstly the ATF, which is in the system gets pumped out, before the refilled ATF gets pumped out - or - and I am afraid that might be the case, that the old and new ATF get mixed before the mix is getting pumped out.
I somewhat think, if it were that easy (as "easy" as on the ZF transmissions, as you describe it), no one would ever have come up with the idea of release, refill, release, refill, release, refill, which is very wasteful.
And I have shown that it is not that easy to get to the cooler connection. But once you are there, it really does not make much of a difference, if your remove just one or both lines, and do it as I wrote: Blow out the old completely, so that you can be sure that old and new does not mix.
Actually, I just remembered: only on the 6hp26 I did it as you suggest - on the 5hp24 I already did the "blowing" with the air gun (carefully, do avoid any damage, because as no one else seems to be doing it that way, I do not know, if it is possible do damage something that way). And I did it already on the 5hp24 that way, because otherwise you have to let the brand new ATF (expensive!) flow for a while longer thru the pipe, until you convinced yourself, that what comes out now is NEW ATF. And because I had both pipes disconnected anyway, because I removed the radiator to do the timing chain swap. So even if the old and new ATF do not mix (as described above), it would waste more ATF to get to the same result of a full flush.
Another problem with the method you are thinking about: You are repeatedly letting the transmission run on empty. I did that on the 6hp26, and many people do it, but I do not think it is without risk.
PS: Plus, the method, you are thinking about, leaves a little bit of old ATF in the cooler and in the pipe from the cooler back to the transmission..., while my "blow method" takes care of that as well.
To sum it up: I did the ATF change the way you propose already on 2 cars: The S-Type with the 6hp26, plus on my Ford Fairlane NL '97. So yes, where possible, both methods are OK, but I just don't think the method you are suggesting is really possible on the Jatco jf506e.
Last edited by Peter_of_Australia; 02-23-2023 at 02:34 PM.
Reason: added PS note
Hi Michael Davis,
Your videos above are in regards of transmissions, which are similar to ZF 6hp26 and 5hp24.
The videos are not about X-Type or Jatco jf506e.
I think that the Jatco jf506e is a different kind of kettle...
I just cannot be sure if basically the "computer data storage principle" FIFO is applicable for the jf506e.
To sum it up: I just don't think the method you are suggesting is really possible on the Jatco jf506e.
The JF506E is the same as all other engine driven fluid coupled transmissions with a detached cooler from a flush perspective. Some hybrids require an electric pump, but most all others use a positive displacement engine driven pump. The largest flow and store of fluid is in the converter. Some converters have a drain plug, but most (including the JF506E) do not, so the only way to flush the converter is to remove it and drain it or push out the old fluid with new fluid. The pump pulls fluid under vacuum through the filter and positively displaces the fluid into the converter and other pressurized feed lines. At idle in Park none of the clutch packs are connecting the input to the output shaft and the fluid flow is essentially only in the pump, converter and cooler. Some transmissions use a thermostatic valve which would not allow fluid flow to the cooler until the fluid is hot, but that doesn't apply to the JF506E. The flush via tapping into the cooler lines works on the JF506E the same as other transmissions, because the fluid flow principles are the same. The packaging is different between a RWD transmission like the ZF 6HP26 (input and outshaft rotate around the same line) and a FWD transaxle like the JF506E (where the input and output shaft are parallel but do not rotate on the same axis), but the pump, converter and external cooling are virtually the same, because there isn't a need for it to be different.
Well, according to that (what you write & and if you are correct), both methods could be applied for the ATF full flush on the jf506e - you seem to have more insight there.
You are mentioning the filter... I certainly know, where that one is in 6hp26 and 5hp24 - but I would not have a clue where to find the filter (and how to swap it) in the jf506e...
Last edited by Peter_of_Australia; 02-27-2023 at 05:46 PM.
The filter is basically in the same location as the 6hp26, right under the pump laying flat submerged until the fluid in the bottom of the trans. However, you can't remove it without splitting the case, so it isn't serviceable while in the car.
Besides the reservoir where the filter sits, the second largest store of fluid is the converter which is upstream of the cooler. As you have found you can't push fluid back through the converter, so the only way to flush that is to push fluid forward (not air backward). The second issue is that when the transmission is 'off' all the solenoids are closed and all the clutch pistons (servos) the pressure feed lines connecting them and the valve body are essentially locked. So there is no real easy way to get all the fluid out, but doing the overnight drain and flushing the converter will get the most old fluid.
OK, but nevertheless - apparently against every logic - I was somehow able to "blow" the old ATF out more or less completely, since I removed a wee bit less than 8L and I filled in a wee bit more than 8L...
@ Michael: As I pointed out in my thread, I was pretty carefully with that air gun, because I just do not know, if or if not it is possible to do any kind of damage by blowing into those 2 pipes with the air gun. While I succeeded in not doing any damage, I still do not know the answer to that question. Since you seem to have more insight into that transmission (or any transmission for that matter): Would it be possible to cause any damage by blowing into those 2 pipes with an air gun?
@ Michael: As I pointed out in my thread, I was pretty carefully with that air gun, because I just do not know, if or if not it is possible to do any kind of damage by blowing into those 2 pipes with the air gun. While I succeeded in not doing any damage, I still do not know the answer to that question. Since you seem to have more insight into that transmission (or any transmission for that matter): Would it be possible to cause any damage by blowing into those 2 pipes with an air gun?
For simplicity sake, one cooler line has to be the low resistance path, therefore allowing flow from a higher pressure push on the other side. This low resistance port is where the fluid returns to the transmission. Generally this return path supplies oil to the bearing, bushings and gears because these do not need high pressure, but they do need volume or flow. I cannot think of any reason why air pressure into this path is really any different than fluid pressure and it should not cause a problem. This also explains why you see more fluid flow in one direction because you are pushing out the fluid in the low pressure lubrication path.
For the other side, the higher pressure side or upstream connection is obviously facing the pump. The trans needs high pressure fluid to control the clutch engagement, and it uses valves to distribute the pressure for various controls. I always try to disassemble and clean these valves when rebuilding the transmission, and I typically use air back pressure or direct force to back out the valves. Sometimes these valves stick when backing out so you have to push them in and out using solvent cleaner until they are free. With the engine off there is no fluid pressure, so back pressuring the upstream port would result in a flow and pressure reversal. I don't know if that back pressure could cause a valve to move out of position or get stuck or a pressure seal to be damaged.
General fluid flow through the cooler from upstream is in the bypass path from high pressure lines. The bypass allows high pressure to be maintained while bleeding of excess volume to move fluid through the converter out to the external cooler and then finally (after the cooler) to the bearing/bushings/gears.
OK, but nevertheless - apparently against every logic - I was somehow able to "blow" the old ATF out more or less completely, since I removed a wee bit less than 8L and I filled in a wee bit more than 8L...
The factory service manual says to drain the trans and refill with 8L. Either that is a typo or an indication that there is 8L of non-captive (drainable) fluid in the trans. Perhaps that isn't practical in the real world and waiting several days to drain along with the assistance of some air pressure encouragement as you have found, can drain almost 8L, but not easily. Others have reported an added 2L drain by waiting overnight, so I don't think it defies logic to continue to drain more fluid over time (and effort). I don't know if it is a repeatable experiment to get 8L out of a properly filled trans, but I think it is clear there are ways to increase the amount drained.
I don't know what the full fluid amount is in the trans and I have seen some trans repair sources say both a little over 9L and a little more then 10L. What I do know is that it is impossible to empty the fluid out of a trans while it is in the car. When you disassemble the parts, the fluid locked behind closed doors spills out on the bench. The converter also has lots of fluid trapped inside. The converter itself is like a jelly filled doughnut. If you poke a hole in the center, you may able to get the fluid above the hole to drain out, but it is impossible to drain the fluid below the hole because of gravity. Fluid is heavier per volume than air, so air is not capable of displacing it. So my main point would be that I don't believe that it is possible to completely remove (complete full flush) the fluid from the trans without removing it from the vehicle with a gravity drain based approach (even including the air pressure assist on the low pressure side).
I do however believe it is possible to get over 8L of old fluid flushed with the above youtube demonstrated methods in about 30 minutes to an hour, and I have done it personally.
> ... so back pressuring the upstream port would result in a flow and pressure reversal. I don't know if that back pressure could
> cause a valve to move out of position or get stuck or a pressure seal to be damaged.
OK, I will keep that in mind and I will continue to blow air-pressure CAREFULLY into the pipe coming FROM the transmission, next time I have to do an ATF change again.
I actually read a lot about the topic ATF change on the jf506e, and I actually do believe that the total amount of ATF in this Jatco transmission is 8L total.
As I wrote above, those, who apply the wasteful "drain, refill, drain, refill, drain, refill"-method report to drain each time 3.3L only (i.e. they would use up about 10L, and they would be a long way away from having done a full flush). I waited quite long and I drained 5.5L. I do not believe, that waiting any longer would result in more ATF leaving the transmission voluntarily...
When I applied air pressure, the old ATF did NOT ONLY exit the transmission by the drain plug (encouraged by the air pressure), but quite a lot also come out of that exact pipe, in which I just blew the air, after I stopped blowing, which could have been exactly that old ATF, you were thinking about - that old ATF, which is trapped one way or another in the transmission.
It will actually not be that long (a few month I guess), until I will have to do a complete ATF flush on another jf506e (on my other X-Type, the AWD). I am not sure yet, which method I will apply...
Thanks Michael, I actually read a lot about the topic ATF change on the jf506e, and I actually do believe that the total amount of ATF in this Jatco transmission is 8L total.
I would definitely not believe everything that you read on the internet. Jaguar says that the fluid is a lifetime fill. If you are the factory, lifetime is 150K miles, but if you are the owner with a car that has 150K miles, you probably hope lifetime is not that short, so both can be true and both can be false depending on your perspective. According the Jagdocs repair manual, 8L is the refill capacity (meaning what you can reasonably extract from the trans) and 9L is the dry capacity. ATSG, the leading AT repair manual producer says about 10L. https://at-manuals.com/manuals/09a-vw-jf506e-2/. I think you have demonstrated that it is possible to extract 8L with an air flush (which I think demonstrates that the full drainable capacity is close to 8L), but you haven't demonstrated a way to remove the captured fluid, to get the remaining 1.5L to 2L. There are two reasons for this. First it is physically impossible to remove water from a well by pumping air in from the top with a drain at the top, because the fluid is heavier and will simply remain at the bottom. So you cannot remove all the fluid from the torque converter. Second, the valve control system is designed to hold back the pressure and only selectively engage the pistons to engage the clutches, so all those pressure paths are closed doors at both ends. The solenoid closes the path at the front end and the piston closes it at the back end. There are several pressure line taps on the outside of the transmission for pressure testing, so you could effectively remove those taps and prove that the inside is dry of fluid I guess.
To get a look at a torque converter, the beloved eric the car guy has a pretty good overview.
So after looking at that, I will leave it to you to demonstrate a method to extract the fluid from the bottom half of the converter using air pressure, because I don't think it is possible with 90psi.
Originally Posted by Peter_of_Australia
When I applied air pressure, the old ATF did NOT ONLY exit the transmission by the drain plug (encouraged by the air pressure), but quite a lot also come out of that exact pipe, in which I just blew the air, after I stopped blowing, which could have been exactly that old ATF, you were thinking about - that old ATF, which is trapped one way or another in the transmission.
Yes, I do think you are extracting some of the trapped fluid with this method. By pushing pressure back into the upstream path, it seems that you are able to get air to accumulate in the top half of the converter under pressure which then pushes fluid out the cooler pipe, when you remove the air gun from the pipe. However, it is a very tedious and messy process, and instead of only removing half the fluid in the converter with a back air flush, you can remove all of it very quickly with a forward fluid flush, which is the standard practice that I am recommending.
OK then, I'll try the forward fluid flush next time on the jf506e..
But the air pressure method is still heaps better than the commonly accepted 3 x drain & refill.
And there was actually nothing "messy" about the air pressure method with oil-catchment-pans under the drain plug & under the pipe openings.
Good torque converter video.
PS: Actually, I may end up not applying any of those 2 full flush (or near full flush) methods next time, when dealing with my AWD X-Type, as the big issue with that one is that I bought it (knowingly) without reverse gear function. Thus, I may end up with the jf506e sitting on the work-bench and I may remove the torque converter - or if even all that fails, I already have a spare jf506e. Do you know, if I can do a full flush of the spare jf506e, while it is sitting on the work-bench, but without taking it apart? In which direction do I have to tilt it to have any chance of emptying the torque converter that way?
Cheers, Peter
Last edited by Peter_of_Australia; 03-05-2023 at 02:14 AM.
Reason: added PS
X-Type ATF change – How to do it utterly thorough...
In my comment just above I mentioned that I might not do any of those 2 methods of ATF change next time, as I may have to remove the complete transmission from my 2.5L AWD 2001 X-Type... - however, meanwhile I would a third X-Type, a 2.5L AWD 2004 X-Type...
Thus, I had to do another ATF change... - Amazingly the previous owner did 1 or 2 ATF changes himself (Btw.: He used - as expected - the 3 x drain and refill method. ), but as he did not even know, which ATF he used, it is obvious that he used the next best multi-vehicle-ATF. I.e. I had to do a proper ATF change, and after the discussion above (with Michael Davis) I decided to do that ATF change this time absolutely perfect:
So to recap – and adding to it:
There are a few different ways of doing the ATF change on an X-Type – and as there is neither a removable ATF-fluid-pan under the car nor any accessible ATF filter, and the pipes to the radiator are more difficult to access, it is more complex than on other Jags – here are the different methods possible:
1. The widely accepted and worst way of doing it (because it is very wasteful and leaves a lot of the old ATF in the system): The 3 x drain and refill method.
2. As I described it above: After draining, remove the x-bar and the 2 ATF-pipes from the radiator and blow thru the radiator-section with compressed air, which cools down the ATF in normal operation, and blow carefully into those 2 pipes and with compressed air and let it drip over night. This, however, does most probably not take care of the ATF sitting in the torque converter (as a bubble-bath does not empty the bathtub, as was pointed out to me above by Michael Davis).
3. Draining of ATF, refilling of ATF and then as above in “2” removal of X-bar and removal of at least one of the ATF-pipes from the radiator, adding a hose to direct the purged old ATF into a waste collect pan and starting the engine briefly to let the ATF-pump purge the old ATF out. The problem with that is that it would not purge the ATF sitting in the pipe going from the radiator TO the transmission, and depending on how you do it, also not the ATF sitting in the radiator.
4. Do both: ""2" & "3"...: I assume that no one ever did such a thorough ATF change on a X-Type (apart from those, who removed and disassembled the transmission): Drain ATF, the blowing the old ATF out as in “2”, then refilling ATF and continue as in “3”… Not many drops of the old ATF would still be in the system after all that!
So additional to the procedure explained at the very top of this thread, here are some more pictures from my latest ATF change:
This time attempted to remove the transmission-pipes on the radiator without removing that cross-bar - that was a no go.
Thus I removed and spray-painted (black cold gal & clear coat) this as well...
Note that it is necessary to insert the pipe-removal-tool fully and to twist it into a position, where it can "push" all 4 clips on the pipe-connector outwards. Then it is time to pull the pipe off while holding the radiator back with the other hand.
So here we go: The "blow" method: After disconnecting the drain plug: With both pipes disconnected and the lower pipe replaced with a "waste-pipe" leading into the waste-pan, I blew with the air-compressor-gun full power into the upper opening on the radiator and out came the ATF, which was stuck in the radiator. Then I carefully blew into the 2 pipes going to the transmission and out came the old ATF by the drain plug opening and by those 2 pipes (2 pans required!)
That's one of the pans. (Btw.: Before blowing: Opening the drain plug only (and starting up the engine twice for about 3 seconds each, and letting the old ATF drip out over night I got 4L out of the system..., "Blowing" gave me another 1.5L after letting it drip again over night).
After putting the plugs (drain- & check-plug) back on and filling about 5L of new ATF Fuchs Titan 4400 into the transmission, I was ready for the next phase: Letting a little helper start the engine very briefly - initially to confirm that the ATF would come out of the pipe, where I expected it - it did not, which is why I placed just pipes over everything to avoid a mess. As it turned out, the ATF came out by the green garden-hose, i.e. the upper pipe was the one coming FROM the transmission... Note that it differs from model to model, where the ATF comes out: the upper or the lower pipe: S-Type: upper, X308: lower, X-Type: upper. As my little helper had only a couple of minutes to help me, I had to contend with the ATF coming out by the green hose (no time to change that).
But the idea was, that it would come out of the clear hose so that I could see the colour-change better, AND the idea was to purge the ATF-chamber in the radiator that way as well: So as you can see, the ATF comes out of the upper pipe, which I connected back to the radiator, and the clear waste-pipe goes to the lower connection point. So after doing the "big purge" while my helper was there via the green hose, I then reconnected the pipes and briefly started the engine again twice (I secured the clear tube onto the tub with a clamp, so that it would not decide to jump out, while I am not there to hold it). As it so happened, that very last bit of ATF came out as pink foam, i.e. the transmission was just about empty again. Good timing.
So I connected the second pipe also back onto the radiator and then I filled in more of the ATF. Initially I filled in 3.6kg, and this time 4kg (I placed the huge 20L canister onto a bathroom scale before and after. The density of Fuchs ATF Titan 4400 is 0.85g/cm3, which is 850g/L. Thus, overall I put 7.6kg of new ATF in there, which equates to 8.94L. This does not mean that I have now 8.94L in the Jatco transmission, as some would have left the transmission-system again, when I purged the system.
When I was done, I started the engine (the car was jacked up leveled), let it run for a short while, went a few times thru all the gears with the foot firmly on the brake and the handbrake on, and then - with the engine running I opened again the ATF-level-check bolt, which is the big golden one on the right side in the picture. A small stream of ATF came out - I was happy with that. If more would have come out, I would have left it open for a while longer, if nothing had come out, I would have filled in more ATF (with the engine running). Then the check-level-bolt goes back on, and only then the engine is being switched off.
All the gears where still working after all that - I thought, I just mention that...
Last edited by Peter_of_Australia; 04-13-2023 at 06:45 AM.