Hi guys, I've been lurking here for a while, but I have a strange issue and would like to hear advice from someone who's more knowledgeable than me as I couldn't find anything like that on the forums. Also, sorry for bad English. I have a 2003 (2004 MY) Jaguar XJ8 imported from Japan into Georgia (the country) with about 90000 miles (150k km) on it, but it came with two shot injectors, so it sat for a while before I fixed it. Unrelated - I also converted to coilovers from S-Type, which worked out pretty well actually, really stable and comfy.

Anyway, to the issue. Usually when I'm cruising in 5th gear at about 50 mph (80 km/h), it will shift into 6th gear with a noticeable kick, which really worries me as I don't want to damage tranny further, and it was always like that as far as I can remember. Diagnostics at a Jag dealer don't bring up any faults, but the best independent transmission specialist in the country assures me that all solenoids need to be changed and that will fix it (he didn't open it up or anything). I've also checked transmission fluid level with independent Jag mechanic and he said it was full and didn't need changing as the color was like new.

Jaguars are rare here, with maybe 10 or less X350s in the whole country, so it's difficult to find a real specialist. So I went to the only official Jag dealer with the TSB in hand regarding harsh shifting fix by resetting transmission adaptations and updating software (file is attached), and after 3 hour wait they said that they are not sure about the procedure as they've never done anything like that. They can try to perform adaptations reset, but I have to waive them from all responsibility if something goes wrong as it is an older car, which frankly worries me a lot.

I love this car, so I wanted to hear your opinions before I do anything. Is it a risky procedure? Can it fry my tranny? Should I just forget about it and drive with a J-Gate in 5th? Please share your thoughts!

 

I've not personally done the TCM reflash, but I know many members here have had this done (especially on the early models) to fix a variety of issues. There's also a shift pressure relearn procedure, in which you have to drive around at certain RPMs and loads and the transmission relearns the correct shift pressure. It definitely shouldn't be harsh in the 5-6 shift, I think that's one of the most imperceptible shifts the unit makes in my vehicles.

There was a recent post by Meirion1 (see #5) with a link to changing the solenoids: https://www.jaguarforums.com/forum/x...n-cold-191169/

 

At 90,000 miles it's overdue for a transmission fluid (and filter pan) change. Although Jag claimed that the transmission is 'sealed for life' ('sealed for the life of the guarentee' [Cynical, moi ?]) ZF recommend that the fluid be changed at between 50,000 and 75,000 miles.

I had mine done at 78,000 and a TCM reflash at the same time and it's much improved.

 

Thanks for the replies guys! I've seen that thread, but I would prefer to exhaust every other possibility before I open up the transmission... I was going to change the fluid as well as I've heard the same about the "sealed for life" deal, even bought the pan, but the specialist said it would make zero sense to do it after he inspected the fluid and I didn't really press him. I'm still inclined to try resetting adaptations cycle first, fluid change would be the next step if that won't help, but I can't really find any info if it can cause any issues...

 

Jag haven't claimed that for 9+ years (which was when I joined TOPIx).

Fluid may fix it but may need a rebuild.

 

I did say claimed, and there isn't a transmission fluid change on the service sheet (that I've seen).

Is the a service bulletin that covered the change to ZF's advice ?

 

It's on TOPIx with details of miles etc dependent on usage, region, etc. They don't usually put such stuff on the short form sheets.

If you understand "sealed for life" as "... life of the warranty when new" you'll be about right. That warranty ended long ago.

 

Thanks for the replies guys! So you think just TCM reflash and adaptations reset won't solve the issue and the TSB is not applicable in this case?

 

Did you get this resolved and how? I am having the same problem with my 2005 xjr. Thanks

 

Hi Asif, local Jaguar Land Rover dealer told me that they won't accept any responsibility if the flash went wrong and that they've never done anything like that so I opted to just drive it as it was as other gears had no issues. I did change the transmission fluid and pan/filter couple of days ago (because I fixed leaking transmission fluid lines that lead to radiator, so I thought might as well) and the 6th gear improved by A LOT, knock on wood, so I would definitely strongly recommend to do that as soon as possible if you haven't done it yet (it turns out that the last fluid change was done in 2009 and the smell was atrocious).

 

I would start with Transmission oil and filter change.
Then do a reset through SSD