My is a 2004 XJ8 with 60,000 Miles. I kept getting the same transmission fault code (transmission Error up shift 2 to 3). I can feel the hard shift at low gears and or stuck in gear. I have a dedicated Jaguar reader and there were times the tranmission information did not even show up. (no communication from ECU to reader).

New transmission fluid, after market oil pan, and sleeve were installed and issue did not goes away. The Chinese made oil pan leaked even with the exact torque and bolts order installed. The plug sleeve did not even fit right, I had to use the old sleeve.

After watch and read dozens and dozens of Youtube videos and forums on BMW, Jaguar, Land Rover, which all used ZF transmission, I bought all ZF made oil pan, plug sleeve, all upper seal sleeves, seal bridge, and ZF selenoids. I took my time and went throught the procedure of remove the body valve to replace all new upper seals, selenoids, and plug sleeve. The first drive after install, the Jaguar shaked and kicked while shifting in all gears . The kicks and shakes were similar to a driver first learrn how shift a manual transmisoin. I contacted Jaguat dealer to reset the transmission adapatation. Jaguar dealer in Nashvile would not service X350 and recommeded a local repair shop. I do not trust an idenpedent shop on Jaguar and decided not to do so . I was about to gave up. I even got another up shift 2 to 3 error code after 100 miles or so of driving. Months later and after couple hundred of miles, the Jaguar adapted itself and transmission now shifts smoothly like new.

The exact cause the error up shift 2 to 3 and stuck in gear. I do not know. It coulld be the the upper sleeves or bridge worn out and leaked;or it could be the worn out selenoids ( they were dirty with lots of buid up). I did not mind spending money on ZF OEM parts since all labors were on me and I planned to keep this X350 for a while. Adaptation reset for trasnmisison was not needed. It just took time for the Jag to relearn. I got my ZF selenoids and ZF oil pan from Rock Auto for discounted price. The upper sleeves and bridge were bought in Europe and shipped to the US.