I know a lot has been written and debated on this subject. I have also seen some pdf's referenced.

I found this video by ZF Services on doing a transmission oil change

I have not seen it mentioned in any of the many threads I read, so I am adding it here. The video was published in June, 2014.

These are the salient points are:
1.) Drain and fill every 50-75 K miles or 8 years. (There is no recommendation made for a complete flush).
2.) Drain after engine is hot.
3.) Replace filter at every change.
4.) Important to position car with the wheels off the ground.
5.) Fill with approximately 4-6 litres (or quarts).
6.) Turn on car to circulate new fluid, then while holding down the brake pedal, shift into reverse, then drive (or 1st, then 2nd, then 3rd).
7.) With engine idling, and engine hot, remove fill plug to let excess fluid drain, or top off if no fluid drains.
8.) Underfilling and overfilling are both dangerous.

Of course, they only recommend ZF fluid and filter/ pan.

-Sax

 

Thanks for posting.
The points listed draw many parallels with the steps most follow on this board.

From what I gather, the most important point is to ensure the fluid temperature is at proper operating temp (between 40-50C) before opening fill plug

 

Not so much when opening fill plug but when actually filling with the car level.. Very important to get this step correctly done otherwise fill level will not be correct.

 

Seems quite simple when looking at that video.
Most important is indeed the right amount of oil, which means both correct levelling and stabilised and controlled temperature in the gearbox/sump.
However better done with a lift than with stands and with the assistance of a second person.

 

There is a problem. That is a BMW they are referencing.

 

Same transmission, same rules apply.

 

I was kidding; Audi, Aston Martin, Ford, and others use these transmissions. They are very tough, better than the Ford manufactured units.
The fluids specified change by the car manufacturer. But internally they are close to identical.

 

Sorry for butting in here, but looking for a bit of advice with respect to gearbox oil change.

I just bought a 2011 XF 3.0 Diesel with 230.000 km (140k miles).

I cannot see from service history if transmission oil was changed regularly or even changed at all. Transmission oil looks pretty dirty. Gear changing seems OK but then again I have no control car for comparison.

I have bought a new plastic sump cover with filter and 10 L oil.

I have been doing some reading and am in two minds about attempting a flush rather than just exchanging the old oil that can be released from the sump.

After renewing sump/filter and oil I am therefore also thinking of detaching the input transmission oil coolant line (tube from transmission and going into the oil cooler at lower front left of car) and placing it in a bucket (allowing me to measure the volume pumped out when engine is running slowly in N). I would let engine run short intervals only before refilling transmission with the corresponding amount of fresh oil. Continue until all "dirty oil" has been pumped out.

Does the above make sense to those of you with more experience than me?

I do not have a car lift but would put front wheels on stable ramps and jack up the rear a bit at both sides to make it more level. This would allow me to gain access under the car. It would not be completely level and I am not sure if this matters so much if I anyway do a flush. Does more oil stay in torque converter if front of car raised?

Thanks a lot for any advice!

 

I did exactly this. My gearbox cooler lines were leaking so I cut off and replaced the flex sections. While I had the hoses off I did the flush exactly how you described. BTW it does not come out slowly. It's a very high pressure pump and will spurt and make a bit of a mess but it will get the job done.

 

As Torrid says the oil will come out under a lot of pressure. In fact if you are doing it on your own be careful that you do not flush too much out at a time.

I had my wife turn the engine on and off while I filled a quart at a time.

 

thanks for your prompt reply Torrid! Glad to hear others have done this and gives me more confidence.

Did you have the car raised properly and was it level?

 

Thanks Jackra! Is a "quart" a quarter of a US gallon? How long did the engine have to run approx at idle for a quart to be pumped out?

 

One more question...

would it be even better to use the return pipe from the cooler to the gearbox? i.e. detach it from gearbox and put in bucket. Reasoning is that the entire oil cooler will get actively flushed under pressure rather than passively "sucked" back into gearbox if the gearbox outlet pipe is detached from the oil cooler.

 

A quart is a shade over a litre. 0 .946+ litre to a quart.

It takes about 1-2 seconds to throw out a quart on my car.

Yes it would be better to use the return pipe.

Separating the two at the gearbox is not so easy as mine were clamped together so I ended up blowing out the cooler with air.

 

Wow, that is obviously a powerful oil pump in there! I will indeed have to be really careful.


You mean you removed both oil pipes from the transmission and inserted an air gun into one of them (output or return line?) and collected what was blown out from the other pipe?
I have a compressor so that sounds like a good option if I have trouble like you had to separate them.

Thanks a lot, I really appreciate your advice and this seems to be a great forum for people like me who have relatively good mechanic ability but lack specific knowledge. I will likely get round to this next week and I will try to take pictures and post.

Bye the way the garage near me in Germany that does the so called "Tim Eckart" oil flush would charge over 500 Euro for the procedure. They also said they would have to charge more if they had to clean the valves directly under the plastic sump. Garage is called "Hetzel Fahrzeugtechnik" near Bruchsal/Karlsruhe, in case anyone is interested (Startseite - Fahrzeugtechnik Hetzel - Ihr Spezialist für Automatikgetriebe). They seemed pretty competent when I was there shortly this morning.

 

It is because of members on this forum that I have been able to get a lot done on my XJR myself.

 

Question on the following:

"5) Disconnect lower Trans cooler line and run to a drain pan
6) Start car and shift thru gears (old fluid will start to pump into drain pan)
7) I plan to let approx 1 quart at a time get pumped out, Turn off car add more fresh fluid repeat until the fluid runs clean. I plan to have 12 quarts of Mircon SP on hand"

I'm assuming that you are still using the fill plug to put the fluid in when pumping the old fluid out. So you pump maybe 2-3 quarts, and then pump put 2-3 quarts, and repeat.

I'just did the filter and 5.5qts (first time at 70k, second at 125k) and used ZF fluids. Since the Mercon is MUCH cheaper and is equivalent/same, I'd like to do the full flush fairly soon (since I just put a new filter in).

Thanks,

 

Another question. The filter/fluid kit included a new connector sleeve. I don't see how to reach it, nor do I see any tab that you press so you can allow it to come out. What am I missing? Mine isn't leaking after 127k miles, but since I got a replacement one....

 

You need to disconnect the wiring loom to the back of the gearbox then when you remove the sump you will see a white clip at the back of the gearbox pull this down and this will release the white connecter now just pull the connector out