The ZF 6HP/26/27/28 has been covered in several other treads. Here is the result of my recent experience. The 03 STR with 80k had a issue shifting down from 2 to first at very low speed and what has been discribed as a "Lurch" addressed in other applications such as the Audi and BMW. Up shift form 1-2 was a 1 and 1/2 shifts, uncertain at best.
Debating whether to keep the car, I settled on a change in fluid, filter and connector sleeve couldnt hurt. This with a complete memory wipe of the TCU had resolved all the issues.

The Jag certified tech advised to be gentle the next few hundred miles as the trans "relearns" to shift and to avoid using the "Sport" feature for the next 300 miles.
The ZF is now the smoothiest auto tranny I have ever owned..this maybe a keeper.

 

I am happy for you , good thing it was not a major issue with your tranny . Sometimes my daily driver (not a Jag) also jerks during 60 -80 km/h and this car is around only 6200 kilometers on the odometer .

 

Great news! Thanks for the update!

 

Thanks Phil. I'm going for a TCM flash due to similar shift issues.

 

My Jag certifed tech tried a simple reflash of the TCU first with little improvement. He advised that a "complete memory wipe" was the next level and he was spot on. The results were well worth the money. BTW the fluid kit came for California Transmssion Supply Company at approx. $200 it included the filter/pan ( usually 200 by it self) 6 liters of ZF fluid. Order the replacement torx bolts ( 21 of them for $24.00 ) and the connector sleeve for $16.00 as well. The fluid change is a bit of process so I left it to the tech who had done this many times. He advised in his 20 years, he had never had to replace a 6HP and was convienced ,early, that a service would solve the issue.

 

I have now done 900mi since my fluid/sleeve/bolts/pan service. Shifts like butta, no lurch and no leaks. I used the Land Rover fluid which is exactly the same at a fraction of the price. Used 5 3/4 litres with a little spillage.

I had an AAMCO tech do the work. Took less than two hours all in with 2 test drives.

 

My 2006 S-type 2.7D with ZF 6HP26 autobox was cured of all its ailments (mainly noises and severe torque-converter clutch shudder) by attention to ATF fluid. Changing the fluid was a pig of a job. Mileage was 120,000. It's so good now, I wouldn't be surprized if it did another 120,000mile.
Leedsman.

 

Do you know if this is the same tranny on my '05 3.0 S-Type? Mine noticeably downshifts when I am slowing down in lower gears. Maybe this will solve my problem? BTW anyone who has done this: What was the final cost all told?

 

AJMianevents,
I have read the 4.0, 4.2 and 3.0 all use a 6HP but I do not know if they are the same series/dash number. If you take it to a Jag tech with the needed diagnositic computer, I would think he could address it wahtever the series. As for total price, I bought the filter kit, replacement bolts and connector sleeve for a total of about $275.00. My tech charged me 2 hours labor and a diagnotics for a totla shop bill of $250.00..best money I have spent on this new toy

 

Good thread. With everyone claiming the problems this service has fixed, seems like it's well worth me trying. At roughly 110k miles, what's $250? I think someone had a video of doing the work themselves also.


Any suggestions on where to order the kit from? I'm currently looking at one website that has a 'Vaico' brand kit(inc. gasket, seal, plug) for $194.

 

Here is the address for the California Tranmssion Supply Co with all the information you ask. Check the Search for a proceedure to change the fluid..it is not simple as other geraboxs.

The CTSC - ZF Parts

 

The transmission specialist who performed the work has done many 6HP26 gearboxes in a wide variety of autos did it a little differently. He pulled the pan and let it drain and replaced the connection sleeve. Installed the new pan and new bolts after cleaning and inspecting the surfaces. Filled it up, ran the engine through the gears, topped up and put in the fill plug.

Took it out for a short drive running it through the gears and put it back on the ramp hoist. Pulled the plug and topped off to a light stream exiting the fill hole until dripping lightly and put in the plug. Took it out for a second test drive and handed me a bill for $150. All done in less than two hours.

I had the same instructions and he read them before he started and said he could do it that way but that is not the way he normally does it. He was happy to charge me for an extra hour to do it that way but he stated it was not necessary. He has never had one fail or improve the 1/2 short-shift or lurch if present. Often caused by low used fluid.

He also concurred that the Land Rover fluid was exactly the same stuff as Jaguar recommends at a fraction of the price. He used 5 3/4 Litres with a little spillage. Exactly what ya would expect.

Shifts and drives like new at 39K miles. No more short-shift and/or lurch.

 

Since the fliud change and TCM wipe then re-flash; has there been a change in shift pattern? i.e. short shift debacle?

 

Much of the Jaguar TIS ( ZF) proceedure is related to thermal expansion of the fluid..which ,as an aero engineeer, I would cannot imagine would result in more than 1-2% of the total volume. If this were a cyrogenic I would not be so cavalier but we are talking mineral oil at ambient temps..
For bfgross: the shift patterns have and are changing as the new patterns are being accepted by the TCU..all a great improvement..never had a short shift issue but the 1-2 up is now very positive and the 2-1 down is smooth and better timed. Now on the the clunk in the suspension and a fresh supercharger belt. BTW the #4 coil quite while we were driving the transmission test,,$65.00 to Jag for a replacement.

 

You need to reflash both TCM and PCM.
No idea what he means and it sounds like he has little clue. "Jag certified"? When and on the S-Type? Doesn't sound like it

 

The 4.0 doesn't use it. It has the Ford 5R55N (which the 3.0 before 2003 also uses).

 

Thank you for the info searanch. Could you please let me know who did your service for you? I live in Calgary and travel to Kelowna regularly visiting friends. I would be very pleased to resolve my shifting problems on my 03 S-Type 4.2. Its been a headache which developed about a year after purchasing the car, developing right after the transmission was dropped to replace the rear engine seal at 64,000 kms. After bringing it back in to the dealer to checked out several times, having it re-flashed and re-checked, had another garage check the ATF level, the shifting problems were never resolved.

Thanks,
Terry
(THEP are my initials)

 

Hey Terry,

A few months after I did the drain, refill and replaced the connection sleeve I got a gearbox fault and had a rebuilt torque converter installed by a different transmission specialist. He used a different fluid and replaced the front transmission seal with a Jaguar seal and not the generic seal for the 6HP26 after it leaked.

I didn't have the transmission re-flashed and it has been working flawlessly up to storage in October for the winter. I would be happy to direct you to the folks that did the torque converter rebuild and we now have Jaguar dealer here in Kelowna if you want it re-flashed.

Let me know if can be of further assistance...