Hey every one. I just turned 100k on the XJ and here come the problems! Just to let you know I did copy and paste the below from another user from a couple years ago but I have the same problem. No I was not in S mode.

Recently My 04 Jag has been getting stuck in 4th or 5th gear on the Freeway. At 70mph the car would be sitting at 4000rpm. I could trick the car into 5th by getting it up to 80mph, and 6th by getting the car up to 85mph.

Anybody have any ideas?

Also, while shifting the car from P to R in the drive way in the morning, there is a loud and heavy bang?

Thank you everyone in advance!

 

1. Does it shift up and down using the manual side of the J-gate ?

2. Are there any faults on the annunciator ?

A TCM reflash may cure your problems, however it looks like you do need to have the transmission checked out fully, and probaby a change of fluid & filter.

 

1-Well, I can shift into lower gears with the J-Gate but when I try to up shift back to 5th or 6th it wont go, unless I floor it to 80-85 first.

2- No faults

3- I had the tranny pan, filter, sleeve, and oil changed less than 8k miles ago. At that time I also got a reflash.


Any other ideas people?

 

The transmission control module is actually inside the gearbox, and there is a large plug connecting it to the rest of the car. Might be worth removing plug, quick clean-up, and replace, but that's the end of my technical knowledge. Hopefully others with experience of gearbox faults will be along soon.

 

Further to my last post, I should mention there has been a fault reported in the past whereby the bolts holding the transmission control lever on the transmission assembly have worked loose. Whether this would cause your symptoms I don't know.

I also checked the Jaguar technical notes, and the TCM receives information via the CAN bus of :-

- throttle pedal position
- gear selector position
- engine torque and speed
- transmission fluid temperature
- brake pedal status
- engine oil temperature
- engine coolant temperature
- wheel speed

Also the gear selection is affected by vehicle cornering - shift to a higher gear is inhibited until back on the straight again.

The TCM has what is called an Adaptive Shift Strategy and uses the various data to decide on the shift strategy for the gearbox.

So it is all a bit complicated, so I suggest you get an expert on autotransmissions to have a look at it.