Sorry. Like BMW's Jaguar's have a closed system. Tranmission fluid cannot be added manually. A certified mechanic or Jaguar dealer... Tramission fluid cost $60 a quart. No Bull.... Transmission leaks are crucial
Sealed for life means sealed for 100,000 miles. The only thing I have read correctly in the answers so far is that there is no dipstick. CORRECT. The rest of what I have read is rubbish.
It is EASY to change the fluid and filter on this gearbox XF 5HP24E (as also fitted to big Mercs and BMWs).
The drain plug is on the bottom of the gearbox sump in the middle and is undone with a hex key. If changing the fluid, make sure you also change the filter !
The fill and fill/level plug is on the rear left hand side of the gearbox (looking from front of vehicle) just above the sump. Don't get it confused with the other similar looking twin plugs above.
The fill procedure is well documented and involves filling to the level plug when cold. Starting up, getting gearbox oil to about 30 degrees C and cycling the gears, Park to Drive (hold for a short while), Reverse to Park (hold for a short while). Once done, top up again to fill level plug to slight overflow and leave until trickling for 1 minute at the finest trickle.
Replace plug and test.
PLEASE look for the procedure on the web which also shows you the pictures too (think it's on www.2carpros.com) and that will help.
Don't listen to people telling you it can't be done. The fluid is only good (at very best) for 100,000 miles. They know not of which they speak. The same applies to BMW and Mercedes who also use this pretty weak and poor gearbox in their large V8 models.
Note, this gearbox has a known problem with the forward clutch drum which normally starts with slamming into gear from a standing start or other strange similar issues. Have it diagnosed before spending a fortune on new fluid and filter which will not help fix the problem.
NOTE WELL :- CRITICAL. USE THE CORRECT FLUID ONLY In the UK it is Esso LT 71141 (Exxon) DO NOT USE ANYTHING ELSE UNLESS IT IS A DIRECT REPLACEMENT.