The threads on these fittings accept a 1/2" pipe female thread. The protrusion beyond the threads would not match up with any adapter at my local Ace Hardware store. If a plumbing shop has no connection that fits, I'll return these to the vendor (or sell them for $25, shipping to any US state included) to someone on this Forum. Let me know if you are interested in case I don't find the proper connector. In that case, I'll use the system that Don introduced in the original post.

Does anyone know how many seconds it would take for a full pan of new fluid to be pumped into the torque converter? I'd really like to know that figure if it is available.

Cheers,

Gary

 

Hi Gary,

Based on your description, I wonder if what you need is a 1/2" flare size connector. Here's a coupling showing the 1/2" male flare thread (left end).



These flare fittings come in at least two flare angles, 37 degrees and 45 degrees, so you may have to figure out which you need, but McMaster-Carr carries a fitting that appears to work with both 37- and 45-degree flares and 3/8" I.D. tubing:





Here's the link to the product info page:

https://www.mcmaster.com/53485K941


In all the research I've done I don't recall seeing that specification, which would vary by engine speed anyway, but maybe one of our other members can answer. Based on how quickly fluid is ejected from the outlet cooler line, I would guess it takes less than 30 seconds for all the fluid in the pan to be inhaled by the pump. That is why I advocate the 1 liter-at-a-time method of conducting the fluid change. It reduces the risk of the pan running dry and the pump inhaling air.

Cheers,

Don

 

Did any of you installed a sight glass on the transmissions and differentials? I started with my Passat’s front diff. The A6 and a BMW is next
[img]blob:https://www.jaguarforums.com/bd20e950-d09f-483e-b6cc-1c5e54d423db[/img]

 

That's an interesting idea. It would not be possible to view the sight glass plug without taking a picture with a phone or using a mirror because of the tight locations of both the e-diff and transmission filler plugs. When you get this done please post some pictures.

 

It is tight. I could only see if I took pictures.


At 40*C

Engine off

 

Attached is a PDF of my recent 6ZF6HP26 tranny fluid change with pictures of most of the steps.

 

This is an excellent tutorial and very much appreciated. My 2007 XKR with the ZF 6HP26 at 80,000 miles was beginning to have clunky 2 to 1 downshifts when stopping, and similar sticky 1 to 2 up-shifts at light throttle. After reading your post I had the fluid and pan changed by our local Al's Jaguar service shop, and the transmission is back to normal and works perfect now. Thanks!

 

Hello. Great post! Did you ever find those pics of the transmission cooler flush out with the air compressor? assembled the whole kit and ready to try the above, but want to be really clear on this step.

Thanks!

 

Hi 04XJR,

Thank you for your kind words and for reminding me. I still don't know what I did with my original photos. but I took new photos while servicing a 2006 XJ8 recently and have added a photo to my original DIY post showing my setup for forcing the fluid out of the cooler and lines using compressed air.

I have also added some information and photos regarding the cooler line retaining plate that I encountered on a 2012 Range Rover HSE LUX with the ZF 6HP28.

Also, I added the size of the cooler line O-rings so they can be acquired from sources other than Jaguar.

Please let us know how your transmission service goes.

Cheers,

Don

 

Awesome! Thanks!

 

Thanks to Don, I have almost assembled my transfusion kit. So if one were going the complete route by draining out and changing pan.... Then refilling just that amount in new pan.....Then starting the exchange. (Which from all above seems to be the best way to get as much old fluid out as possible) So how much fluid should one have on hand to attempt this? I have 12 quarts of LG6 (bought before I learned about Mercon SP) I guess I could supplement and buy a few quarts of SP locally but id like to not do that.

 

At least 14 quarts is my suggestion.

If you spill some for watever reason you will wish you had more.

 

After getting a few quotes I plan to do this myself. I want to make sure I get a full fluid change and I have little faith I would get that from a Merc/BMW/jag shop.

Unfortunately I already bought the pan and ZF branded fluid. I'll be supplementing with the Ford stuff which seems easier to find from some quick googling.

For those looking to source the parts from OP's list here is my cart from Menards. I also ordered the Mityvac 7201 . $28.17 for lines/fittings, ~$95 for Mityvac from Amazon.

Took a few hours to compile this, hopefully it saves you as much time.

 

I'm not a Jaguar owner but I have an Audi Q7 with the ZF8HP. Those same lines on the Audi lead to the transmission cooler. I have purchased to fittings on Ebay that connect to the transmission cooler line connects. I needed to Dremel the fitting slightly so that it could seat all the way into the coupler. Now I simply need to attach hoses to the barbed ends and do the fluid exchange. Just another way to skin a cat.

 

Here is the entire cooling circuit on the Audi

 

Hi cgpd7507,

Thanks for the information. We will be grateful if you will report back after the completion of your work and let us know how it turns out.

Cheers,

Don

 

First time poster here, I don't have a Jaguar, but a BMW, but we share the burden of maintaining our ZF's, and after substantial research on alterative ways to do a full transmission fluid replacement I've found this thread to be one of the most useful.

I'm chiming in here because I've found something I believe readers here will be interested in, in particular regarding this exchange ("..." eliding in quotes is my edit, for brevity):

I think you both will be interested in seeing this thread about modifying a sacrificial ZF pan as a flushing device, it seems to have had little attention paid to it where it was posted. I only found it by using some of the terminology mentioned here as search terms ("pump inlet" in particular).

It seems to me as someone who's tried none of the methods here, but has studied the posted DIY's that this one's the best combination of all of them, since:

• You don't need to disconnect the cooler lines, DIY the connectors for those etc.
• You get most of the hardware already "for free" since you need to replace the pan anyway (to replace the filter), hooking a hose to the inlet seems relatively easy. It seems like the easiest of all of them, and the most foolproof.
• It addresses Don B's concern with tomcoo's method nicely: You won't run the transmission with the pan off, so there's no mess. You will run with a hole in the pan, but that's trivially directed into a closed bucket or other receptacle.
• Unlike tomcoo's method you don't need to DIY something to hold your modified inlet in place, as you've got something even better, the OEM pan itself. You thus ensure that it's exactly centered, and that the inlet itself won't pop out etc.

​​​​
​​I did my first transmission fluid change in my 2009 BMW 5 Series today, just short of 200k kilometers. I used none of these advanced methods, but I'm planning to modify the removed pan to do a "flush" in a few more thousand kilometers / few months.

The one thing that seems odd to me in that guide (I'll ask in that thread, but given the age I don't expect a replying) is that the poster used an ATF resistant hose from the pan to their DIY'd ATF reservoir.

I assume that it's because they just had that hose lying around and "why not?". As I understand it you'd usually use such a hose for anything that needs to deal with the ATF at operating temperature, as it might melt or erode other materials, and you certainly don't want dissolved hose material in your ATF.

But in this case the hose is just for feeding the pump inlet with "cold" fluid from the feed reservoir, and as you're using it as a one -off to flush the old fluid your ATF will also be cold (assuming you don't "speedrun" this after a long drive), any ATF that splashes on the DIY'd inlet in the pan shouldn't even reach 30-40°C.

So a garden hose should be perfectly fine, and I'm planning to use either that or transparent PVC when I DIY my own version of this.

Another modification that seems sensible is same sort of vent valve in that inlet hose to purge any air pockets between the inlet and the DIY'd ATF reservoir sitting next to the car.

By adjusting the height of the reservoir you can ensure that before you start the car the hose is primed with ATF at the same distance from the inlet as it would be in the OEM pan. A transparent PVC inlet hose would make it easy to inspect that, and a purge valve close to the pan would help vent any air pockets that would prevent the fluid from equalizing to that level.

​​

 

Hi avar,

Welcome to the Jaguar Forums! It's great to hear from you.

I like ripley's fluid change method a lot! I assume I may have missed it, but I don't think ripley explained whether he had the pan drain plug open or closed while he added fluid. I assume he had the engine running so the transmission pump will inhale the new fluid, but he doesn't expressly state this either. I know from experience that the transmission will not accept much fluid by gravity alone.

If the drain plug is open and the engine running while the new fluid is added, it shouldn't take 16 liters of fluid to do the flush, especially since around 3 to 5 liters will have already been drained prior to removing the pan. Off the top of my head, you should be able to run maybe 6 liters through, allow all the oil in the pan to drain out, then drop the modified pan, install the new pan/filter, add fluid till full cold, then follow the fluid fill procedure per the ZF procedure.

One serious concern I can think of initially is that since there is no filter in the circuit, any debris introduced into the transmission could find its way into the valve body and clog or partially clog a valve or small passage. So extreme care would have to be taken to be sure the ground conical tip of the hose had no residual rubber crumbs, the modified pan had zero particles remaining, the fluid bucket was likewise surgically clean, etc.

Another thing to keep in mind is that it is a great idea to replace the cooler line O-rings during your transmission service, so if you're going to disconnect them anyway (it's easy), the cooler line method is also worth considering, especially now that the "official" flush fittings are more affordable. I need to edit my original post to include information about them since they are what I use now.

Thanks for sharing the link! This gives us yet another great option from which to choose!

Cheers,

Don

 

Hi Don! Thanks for the quick reply. Re-arranging & snipping it a bit for the purposes of my reply:

The "DIY pan" guide needs to be read in the context of this general ZF fluid change DIY, posted on the same forum, which is basically just an illustrated version of ZF's official documentation. I.e. drain, replace pan, fill, then turn on the car and do a "hot fill" once you're at 30-50°C etc. I understand your "by gravity alone" to mean that you can't fill the transmission just by pumping oil into the fill plug with the car off, that's correct, you also need the "hot fill".

It's not discussed explicitly, but you can see from the photo that shows fluid gushing out when he's filling it with the DIY'd pan that the drain plug is closed, but functionally it's "open" (in scarequotes). This is because to get the fill hose into the inlet pipe he's drilled a large hole into the outer plastic of the pan immediately below the oil filter material.

So when the transmission is dumping oil into the pan that oil goes into the inlet vanes leading to the oil filter, but instead of going through the filter and up into the inlet pipe it just gets dumped out into a bucket.

But that part is just an implementation detail, you could also close off those inlet vanes to oil flow, e.g. if you did this by stuffing a bunch of JB weld or similar in there to keep your extension to the inlet pipe in place. In that case you'd open the normal drain plug and have the oil dumped out through there. A slight advantage to doing it the way the guide suggests is that you'd end up with a fully drained pan, as oil will lower than the drain plug there's always some fluid left in it after draining it, but again, a trivial detail.

Yes, I'm not sure how he arrives at that number. I suspect he just means that he had that much fluid on hand, so he decided to let it run through longer to get rid of more of the old fluid. As some back-of-the-envelope math (liter amounts from fuzzy memory of stuff I've read)

1. There's 10.5 liters in the system in total, including the cooling circuit
2. Opening the fill plug and draining the pan gets 5.5 liters out, now there's 5 left.
3. If you do drop the mechatronic that's another 2-ish liters left I believe (service kits for BMW's at least are usually sold as 7 liters of LG6), then 3-ish in the torque converter you can't drain out. So 5.5 + 2 + 3 = 10.5 (close enough).

Now, since he's basically doing this twice he ends up with:

1. An initial "loss" of 5.5 + 2 = 7 as he opens the pan, and drops the mechatronic.
2. He needs to use another 3 if we're assuming no losses to push out the torque converter fluid.
3. That leaves 6 liters unaccounted for (total of 16).

I suspect he just ran the transmission for just short of a minute to go through all the gears. Looking at the pictured setup it looks like he may have done this alone. In that case you won't see when the fluid that's being dumped out clears up, and instead you're keeping an eye on how much replacement fluid you have left in your reservoir, which he's got by his driver's side door.

I also have no idea how much the fresh oil mixes with the old as it's run through the transmission, e.g. when it enters the torque converter whether new oil coming in cleanly replaces old oil, or whether part of it is mixed before being run through. The less "clear" it is the more replacement fluid you'd need before you're happy with the egress fluid looking close enough to the inlet fluid.

That's a good point, yeah you'd obviously want to make sure everything's clean. It would be pretty easy to add an oil filter just before the inlet (just splice some junkjard oil filter housing to your inlet plumbing), but I'd think it's not needed if you just make sure tools are clean beforehand.

Yes, for sure, and in particular if you've got tooling for hooking into the cooling lines already, or find that easier. I just wanted to note that there was another method, which at least to me looks easier, but it may or may not be.

One thing I do wonder is whether a given ml of oil going being picked up at the oil inlet is guaranteed to go through the coolant lines on a given pass through the transmission, or if only a portion of it does so. Attached are oil flow diagrams for 6HP19 which I had at hand (from ZF's repair docs), I've got the M-type in my car. I can't understand it, and I've unsuccessfully searched for some videos or pictures of how the 6HP pump works exactly, i.e. after the inlet is all the oil going to pass through the cooler, or is it only one path, with other parts being flung about the rest of the transmission? There is an AT thermostat, so presumably however it works it'll have to deal with ATF not being circulated through the cooling loop, but still needing to flow through the transmission.

 

Hi avar,

I understand now how the fluid drains out through the sawn hole that is larger than the O.D. of the rubber inlet hose. Thanks for the explanation.

Regarding the oil flow through the transmission, it's a mystery to me too, but obviously when the transmission is in Park or Neutral, the valve body passages related to forward or reverse gears do not see fluid flow, which is why the instruction to shift through the gear positions is important., to ensure the fluid in the valve body is changed.

I remember measuring the volume of fluid in the cooler one time but I can't recall if it was about 1 liter or 0.5 liter. I think it was just 0.5 liter. So regardless of whether all the fluid passes through the cooloer on every cycle or not, the fluid in the cooler is going to be flushed quickly. When you do the flush via the cooler lines, you can see that the flow created by the pump is quite impressive. I haven't measured the actual flow, but to expel a liter of fluid probably takes less than 30 seconds. Maybe less than 15 seconds.

Cheers,

Don