X308, XJ8, Sovereign, 3.2L, 1998/99, AJ27 engine, AUTOMATIC, Transmission: ZF 5hp24

Here - more so than ever, I need to point out : "This is what I did: I am not to be held responsible for damage or harm you cause by getting inspired" - because I did the full flush here differently from how it is done elsewhere.

Normally I find myself the pipe coming from the transmission and going into the radiator (on S-Type: upper pipe / on X308 LOWER PIPE!) and I let the oil-pump in the transmission do the work by pumping the remaining old fluid out by that pipe, after having had removed the pan, swapped the filter, refitted the pan, and refilled the ATF in the transmission (engine running). This is how I did it on the S-Type:

https://www.jaguarforums.com/forum/s...s-type-264102/

Similarly I could have done it on the X308 (but make sure you connect a hose to LOWER pipe when draining the addl. ATF from the system, as mentioned above!), but I came up with a new method, which I think is better. It worked for me, but I cannot promise that one could not do damage that way...

THE NEW METHOD:
Now, since I did this ATF change (full flush) while I had to remove the radiator anyway, but not the A/C radiator, (to swap the timing chains, etc.) I had had both pipes (from and to the transmission) removed from the radiator anyway. Position a waste-oil-pan under the pipes, when you do so... I removed the ATF from the transmission (release plug in the pan): That was about 5L dripping out over night, then I put the plug back on. Next - and that is new: I used my "air pressure gun" and I blew CAREFULLY air into both pipes - one after another. I did not pull the trigger completely and I intentionally let a bit of air-pressure escape from the spot, where I was sticking the gun into the pipes (as I did not and still do not know, if full pressure could cause any harm to the system). The idea was that I would be able to force the old ATF, which still lingered in the system - especially in the torque converter - back into that section of the transmission, where the pan sits underneath. Well, I did that and about 2 weeks later (because I was busy with the timing chains meanwhile), I opened that ATF release plug again, and was pretty flabbergasted: ATF cam rushing out! Plenty of it. About another 5L. Obviously, there is not need to "wait" for 2 weeks, but I would leave it over night. And as I removed the radiator completely, I tilted the radiator to get the remaining ATF out of there, but there was really not much in there, as both pipes were removed before and whatever was in there came already out, while the radiator was mounted in position.

The automatic transmission fluid (ATF), which is required for this ZF 5hp24 5 speed transmission is either: ZF lifeguard fluid 5 or Esso LT71141.
Having said that: There was a merger between Exxon and Mobil in 1998. Esso is a trademark of Exxon Mobil meanwhile, thus Mobil LT71141 is really the same. I ordered 20L of Esso LT71141 and received Mobil LT71141 instead.
It was not cheap, but a wee cheaper than Lifeguard 6 (for S-Type 6hp26), and quite a bit cheaper than Lifeguard 5 (also good for X308 5hp24).


Step 1 - as you should do it - but I always forget (and do it later instead): Loosen the filler plug (do not open, ATF would splash out, but loosen - just so that you know that you are able to remove it later for refilling). Note that there are 2 similar plugs mounted higher up - those are NOT the filler plugs!


My way to do so was finding a relatively small Allen-key and putting the longer end into the filler plug, while attaching a pipe as lever onto the short end of the Allen-key. I think it was an 8mm Allen-key.


This is the transmission after release of the ATF, after removing the pan underneath and after having removed the ATF-filter already (2 torx bolts for the filter).


That is the new ATF-filter fitted. Do not forget to fit the rubber seal onto that pipe-shaped "thingy" pointing upwards (cannot be seen here, as fitted already. I think the recommended torque for those bolts were 10Nm, Well, when I tightened them, that seem excessive. I tightened them with 8Nm - should there be a leak, I will simply re-tighten them. There is a recommended order in which to tighten them: As always on rectangular shapes: From the inside out (i.e. from all 4 "insides" to the corners).


There was a lot of nasty black dirt on the bottom of the pan, obviously especially around the magnets. I cleaned up everything and I attempted to lift the pan up like is was: With the new gasket in position so that I could screw it back on: Impossible! The gasket did not stay in position. My solution was to use minute amounts of gray gasket-maker around the holes on the pan, and stick the gasket on, so that it stayed in position, while I screwed the pan back on. That worked. Another way is to put all the bolts thru the gasket from underneath, before moving that "pre-assembly" under the transmission to screw it on. Don't forget to put the magnets back into position before putting the pan back on.



This is my shiny old pan fitted. I sanded it off with fine sandpaper and coated it with clear coat. Next I filled the transmission up again ( as much as possible, about 5L) via that filler plug (removed) and using a clean transfer pump.


The 2 pipes were still not connected, because I wanted to try something else as well: With the new ATF refilled I tried (with a second transfer pump (one for dirty fluids) to pump something out of both pipes. A wee bit came out, but really not much. But I had the impression that I was able that way to fill more volume in the transmission with new ATF, maybe even into the torque converter.


That is the dirty transfer pump as described above. So after that I refilled more of the new ATF by the filler plug. And I removed the "dirty" transfer pump and instead...


...instead I attached hoses to both pipes (I was fairly confident that I would not need the hose on the upper pipe, but I did that just in case I was wrong and the pipe FROM the transmission was the upper one, but it was indeed the LOWER pipe, where the old fluid COMES FROM the transmission. And I asked a helper to shout as soon as fluid came out by any pipe after I start the engine (first engine start after timing chain swap! ) and I immediately turned off the engine, when the fluid came. That is the picture you see above: Minute amounts of dirty ATF in the plastic-pan and most of that was old oil caught in my PVC pipe from before (Plus note my method of making sure that the pipes are not splashing around like loose garden-hoses, when the ATF comes rushing under pressure!). And as you can see: The PVC pipe has now very clean ATF. That is just what I wanted to get confirmation of: CLEAN ATF! Straight from the transmission, which means that my new method worked - the method of forcing the old ATF back to where I can release it via the release plug!

I reckon that this method is way easier: You do not have to start the engine, refill new ATF, start engine, refill new ATF and start engine and refill ATF. And because you do not have to do that, you also save on expensive new ATF: When doing this "Start/refill" on the S-Type, I needed about 13 or 14L new ATF - mainly, because some of the new ATF would mix along the way with the old ATF, and you have to purge that too, plus you tend to purge a bit more, just to be sure that what you see is now indeed clean ATF.... Assuming the volume of ATF in the S-Type and X308 is comparable, I saved quite a bit: I needed only 10L for the X308 full flush as described above.

So next I reconnected those 2 pipes to the radiator, pumped in a bit more new ATF into the transmission.
With the car safely jacked up and level, I started the engine, and with a drain pan under the car I filled more new ATF until it finally came dripping out. With the engine running I re-attached the filler plug. Did a test drive to get the temperature of the ATF between 30 and 40°C - and with the car safely jacked up level again and the engine running again, removed the filler plug, to check, if the ATF still wants to drip out. It wanted, so all good (otherwise I would have had to fill in more new ATF). So Filler Plug back on, and then engine off. Job done.

But again: Note that while it worked very well for me and that I applied this air pressure very subtle. Would be great, if someone could confirm, if or if not it is theoretically possible to cause any damage by applying air pressure that way...

The advantages are obvious: It is easier and you need less new ATF.

 

Good job however Never flush a transmission unless fluid was changing on time as the manual say if changing transmission fluid was skipped then keep it and check it every now n then if it's low then fill up

 

Thanks, but I fail to see the logic in that. If an ATF change is due, do a full flush. If it is overdue, do a full flush and don't half-burry your Jag in a grave instead.

The guideline of when to change the ATF, changes as fast as the weather anyway; Once it was advertised "sealed for life" - but we all know meanwhile, that that meant really: "Sealed for death".

The logic, not to change the ATF, if it is really old and dirty makes as much sense to me as: "Don't ever clean your house again, once it is really dirty..."

 

The logic is in its viscosity. Older fluid carries with it, minute pieces and particles of the
transmission that help an aging transmission to shift correctly. It is counter-intuitive,
however I have seen some change fluid just to replace transmission after having done so.

 

Thanks, Randy, for explanation of what the motivation of not changing very old ATF is.
I still would never act in line with this motivation. Also: Who is to say, when exactly the point of "too late" for ATF change is?
The valve body is a maze of a lot of narrow channels. All the old particles give the ATF a higher viscosity, i.e. it is thicker and more resistant to flow.
I would compare this with plaque build-up in your arteries due to high cholesterol.
The viscosity of ATF is fairly low on new ATF, that is design-intend.

And obviously I cannot know about the details of those, who damaged their transmission by changing ATF: Did they do everything correctly? Did they do a full flush? Did they use the correct ATF?

 

This is just a single data point, but my transmission was never serviced up to 110,000 miles before I replaced 9 quarts of the fluid for the first time. After the change it didn't slip. So you can likely change the fluid up to around 100,000 miles, but I wouldn't do it if it has more miles than that for the reasons that RandyS mentioned.

I have seen more than one car (not jags) with ~150,000 miles get its fluid flushed for the first time and then start slipping because of the lack of friction material in the fluid. In this case, it's just better to keep the old fluid and ride out the rest of the life of the transmission; it's better to have a car that moves than one that doesn't.
Some things you can do at these high mileages are
1: just do a change, only replacing part of the transmission fluid.
2: keep the old transmission fluid and (as much as it breaks my heart to put that gunk in the car) put it back in if the car starts slipping.
Transmission Stop-Slip may also be an option but I've heard conflicting testimony regarding it. I believe it's mechanism of action is just increasing the viscosity of the fluid, thus increasing pressure on worn out clutches and allowing them to grip a bit better.

 

Well, I can only offer those "data points":
X308 1998/99: 140.000km = 87.000miles (I am sure, looking at the old ATF that no one did an ATF change before). I put Mobil LT71141 in. No issue.
S-Type 2004: 166.000km = 103.000 miles, old ATF was reddish, i.e. someone used before some kind of low quality unsuitable multi-vehicle ATF, I put Lifeguard 6 in. No issues.
X-Type 2006: 173.000km = 107.000 miles: Nearly 2 years ago I replaced reddish ATF (see above) with other reddish ATF (on one hand I did not know any better back then, and on the other hand there is no correct ATF available in Australia for the X-Type. But in a few days I am going to buy another ATF, which I reckon is better (Fuchs Titan 4400).

I also once heard that 150.000 or even 180.000km might be the time for an ATF change - that is 93.000 or 111.000 miles...

But I would not give up on a transmission with older ATF just yet and do a full flush with new ATF anyway, but asdf (thread above) has a point:
Just in case that you should experience indeed slip issues after putting new, correct ATF into your transmission...: then and change the ATF simply back again (new out, old in), so yes, keep the old ATF and most of all: Have in mind to do your best not to contaminate the old ATF for the moment being: I.e. use a clean(ed) waste-pan, clean off first every bit of dirt under the car, which the old ATF could potentially flush into the waste-pan when purging it, do not let leaves, etc. fall into the old ATF. Best fill it from the waste-pan into CLEAN bottles asap and do not discard the nasty residue.

Alternatively, (you may still have the old fluid or not) if you have indeed that slip issue after ATF change, you could experiment: Check the viscosity of the OE fluid (you find it by typing MSDS and the name of the ATF into google), and use instead another multi-vehicle ATF with a higher viscosity. Normally, I would not do that, but if that is a way to bring a dead horse back to life...

 

I'm redoing my transmission oil change because of my mistake with the fluid. Thank you for this thread, it'll probably save me $70 in fluid.
Any ideas on the cheapest way to get compressed air?