edit: adding car deets
X308, XJ8, Sovereign, 4.0L, 2001, AUTOMATIC, Transmission: ZF 5HP24

From what I understand our transmission fluid is “sealed for life” however we know now that may not be the best case especially if youre trying to maintain the car for a long period of time.

i currently have an 2001 xj with 50,000 miles. Although its relatively lower mileage, the oil is still 22 years old. Looking for opinions on whether or not to change the transmission fluid? Transmission still shifts really well, nothing of concern but 22 year old fluid kind of sounds risky.

edit: adding car details

 

First, may I suggest going into your User CP and simply putting in your vehicles information and your location. NA and EU vehicles have different products available that other members could help with, to include possibly a local Tech to resolve it. Makes it easy on all of us for quick reference vs reading a thread.

The sealed for life scenario is a joke, oil products break down over time and with the wear of operating machine parts, you have to get that out of unit and the filter has to be changed. Your ZF trans is very well known for shift issues because of a poor valve which is up-gradable. Here is the part and it's a simple job if you have any technical skill...https://transgo.com/product-details/...ulator-repair/
To look up on changing the fluid, do a search for ZF 5HP transmission fluid change. There is a ZF tech on YT that covers the different ZF versions. For instance the 5 in the model code is for 5 speed....https://en.wikipedia.org/wiki/ZF_5HP_transmission

The trans was used in many vehicles, so you'll see reference to BMW, Merc, VW...etc.

Watch this video...it's only 4 minutes, I've posted it many times, Gary lays out an existing issue and others if they are not headed off to include a cracked shift body which a member here had to deal with a total break down of the unit to get to it and the replacement isn't easy to obtain apparently....

 

thank you for the advice - just added a few deets via the CP.

i have heard the ZF on the non XJRs (like mine) have weaker transmissions so it would be great to avoid the headache down the line and install the upgrade you mentioned (definitely appreciate that)

now I just have to decide whether this should be DIY or should I just take it to my jag specialist.

Do you have any insight on whether this should be a flush or a just a fluid change?

 

With 50k on her and it being her first in 23 yrs, plus the oil product break down I mentioned, I'd flush it all. I don't recall if the '01 had a plug on the converter or not to get a full flush?

You may want to consider your Tech doing it and have him/her, check out everything while under there. To include the center bearing and jurid couplers. Review this thread I made for the reason why... https://www.jaguarforums.com/forum/x...g-info-188400/ ...post #3 shows the jurid couplers. Note the center bearing float band break down, that is a oil product as well....it dried out and gave way.

 

Be aware it’s a messy and frustrating job to change the fluid and there’s no real way of gauging the fluid level in the zf5hp24. The filler plug is on the side of the gearbox with a small gap between it and the exhaust pipe. As you have to have the engine running to top up it gets hot and getting the plug back on before the fluid you’ve just put in co,es out again is a fine art.

I’ve had two of these transmissions fail on me and I can’t recommend the Transgo valve enough. Have it done by a professional place though. I had it fitted on my last XJ8 and the car is still going strong.