Thanks very much for the info and feedback.

 

Hi,
my XJ8 shows the same hunting symtoms like yours.
But how can I find out, what gear is actually beeing used ? Is there a display ?

How can I find out, whether my gearbox has the latest SW ?

( I`m going for an OBD2, if this helps..)

 

Well, here I am another 12 months older, and the car still hunts ! I have now got used to it, but Jaguar really committed a boo-boo with this one. It is only really noticeable on a light throttle at relatively slow speeds and once the tranny fluid is warm, disappears. My car is now on 62k miles and I started with it at 30k miles. The hunting is not a gear change, but the torque converter locking and unlocking.

Clearly whoever wrote the control program is an idiot, but there you are. Maybe he can come on this forum and confess sometime.

 

You described my symptoms perfectly. Had the tranny software updated two years ago and it didn't really fix anything. It seems harmless enough, the torque converter lockup clutch locking and unlocking. There's little torque being transmitted by the engine when the phenomenon appears, and so there's little wear on the clutch.

I've learned to ignore it and my quality of life is much better now.

Mike
2004 XJR

 

Anyone here experience the downshift chirp/groan at low speeds.

I was told there is an additive that eliminates this.

Also does anyone have the additive part number for the steering wheel squeak, which is really one of the rack end seals squawking and transmitted to the steering wheel?

 

Not me (yet !!).

 

If you mean that little shock you get, wenn slowing down speed to less than 5km/h, I experience the same.
Seems like the gearbox suddently gives up its fight for thrust, which causes this shock.

My obd2 shows no errorcodes of my car,, but how can I make the gearbox smother... ( I know this can be accieved, because a similar XJ doesn't shift that hard.)

 

I recently had the tranny serviced by my local Jaguar specialist. It was not cheap, mainly due to them using a lot of fluid to make sure it gets to all parts, incl torque converter. Box is now very much better, with much better changes.

Hunting syndrome on warm-up is still there, however !!

 

did you ever get any answers to your above questions as my '05 4.2 executive does the self same things. cheers, rod.

 

No I did not.
Jaguar parts know nothing about this and stated they have no TSB or service information on it.
So we live with the squeaking..

 

TSB JTB00055 for steering wheel squeak.

Additive is C2S 48887

https://www.jaguarforums.com/forum/s...-sqeeky-76948/

 

Wow, that was fast.
Thank you very much!!

 

I got the additive from SNG Barratt - UK Manchester, NH
They ordered it for me, I am not sure if they will stock it.

 

Does anyone know about the vin break on the 04xjr at G13490. It appears there is a somewhat different tranny from that point through 2005. Does anyone have info of the differences and can they be substituted without major work ?

 

i am having problems like this also --a 05 vdp with 154k miles only does it when warm i think --surging,hunting, lurching only under slight acceleration also there are 2 noises a small chirp going from 4th-5th gear and when it hunts i get a harmonic noise --like bad pavement or rumle strip--very small rumle strips

 

This is an old thread, but I expect that the problem will come up again as our cars age.

I had a similar problem at 120k. Took it to the dealer --twice. He said that there was a generic error code for transmission failure and told me I need a new transmission at $7,200. I was skeptical so I took it to my independent who services my Other cars. He put the car on a lift and noted a leak at the pan gasket. Bottom line is he put in a new pan and gasket, filled the fluid to the proper level and the problem was cured 25k later the transmission is still running fine. I suspect that the car was never put on a lift at the dealer and he just relied on the gnereic code, which didn't really tell him anything -- except he could make a 7K plus labor sale if I was ignorant enough to listen to him.

The ZF transmission is a pain to check/refill and he was just too lazy put the car up on a rack to check the fluid level, This was something any novice mechanic would spot. Obviously, that wa the last time my dealer will ever see the car.

I'm a former PC technician. The procedural protocol for diagnostics is the same I.e.: Diagnose the problem before you "fix" it. Just replacing parts is a disservice to your client. I also learned that the diagnostic tools for computers were not perfect and were rarely definitive of a mechanical problem.

Bottom line, if a mechanic tells you as error code indicates a serious problem, ask him what he has physically done to the car to verify it. Sometimes the most obvious and simplist solution is the one that works. A $10 gasket saved me 7k a least.

 

Just to let y'all know that my car still hunts as I described four years ago in 2012, and the car is now on 104k miles !


And so we motor on.....

 

well just ordered the oem kit zf filter /oil/5 screws -ect.hope to get it done this weekend

 

I hope that works for you. It did for me.

 

The Bosch Mechatronics, in conjunction with the ECM determine the way in which the trans will shift. During warm-up (most noticeable at around 40MPH to 50MPH) the torque converter lockup is applied and released, as I understand it, to assist in trans warm-up. I have also heard it is done to meet SHED testing for emissions reasons. Whatever that reason may be, I do notice that when the ZF reaches 50C, it does change the way in which the Mechatronic deals with the torque converter.

As I understand it, the local dealer can flash the ECM to reduce this.