Hi
I have a 2003 xj8 with 125K on it 4.0 NA. I purchased it as a bit of a project with transmission issues. It was stuck in limp home mode when I got it. I took it to a jag dealer who diagnosed a TCM failure. I purchased a TCM from ebay an installed it. Now it does shift (which it did not before), but when you put your foot into it the transmission shifts into infinity mode when it upshifts. It will work fine when you are on the highway but when you go to start out again it does the rev bang thing. I have also changed the filter, oil and installed the transgo kit. The oil I changed looked good and there was no filings on the magnets.
Do you think the TCM requires a reflash, and would this also be related to the P0730 code I am getting.
Thanks for reading my long winded query.
Cheers
RAM

 

A replacement TCM sometimes requires an adaptation, especially if it isn't exact numbers match. I'm surprised you don't have a 'wrong part fitted' message.

 

If your original problem was the P0730 it is doubtful that your original TCM was the problem.
If it wasn't and you are now getting the P0730 then the TCM is probably still not the problem.
Below is the listing for P0730 and I would first go for the fluid level check. As you can see none of the symptoms are directed toward the TCM.

 

That doesn't sound good, with a new TCM and valve kit you still get this? I would check the valve body in the trans for cracks at this point.

When you replaced the TCM did you do a hard reset and carry out a trans adaptation process? I'm not sure if there's one for the ZF but there is for the box in the XJR.

Questions on the TCM, is it a part# matching module? what are the part numbers for both TCM's?

+1 on Avern's suggestion of level check, but I think it maybe new/rebuild transmission time.

 

OK here is a little more info.
The PN for the original TCM was LJD2401AC00D, so as directed by the Jag parts guy he told me that LJD2401AB was the direct replacement as the original TCM is no longer serviced.
After installing the used TCM I did a hard reset, the car now actually shifted into all the gears and drove nicely on the highway. But when I came to a stop and tried to drive forward I got the dreaded clunk into gear and the limp home mode reared its ugly head again. When I turned off the car it seemed to reset and started out normal again. But now I see the P0730 code.... A retired Jag mech suggested that it might be that the torque converter is draining down?? I have checked the trans fluid after the new filter and oil and transgo installation and about 1/4 litre of fluid came out. Any suggestions on my next move? Back to the Jag dealer for another $176.00 hourly charge for another diagnostic or start replacing solenoids in the transmission?

 

I am not familiar with the transmission adaptation? Can some one explain how this is done?
RAM