Hello!

I purchased my 04 XK8 a little over 2 years ago, at that time with 38k on the clock. I have now just crossed over 48k. During the first year of ownership I noticed that when I came from a dead stop and went to accelerate there was some "pull" or hesitation going from 1-2. If I really hammer the accelerator I would get a "whine" from 2-3. My mechanic had advised that this wasn't a huge deal and just because the vehicle was 14 years old. This was always after 10 min of driving when the car was warmed up. The issue seems to have gotten more frequent the last few months having it out again this season. I have been reading on here that owners with the 6-speed auto T like mine have experienced similar symptoms and most have stated that a pan-drop-replace transmission fluid change usually fixes the issue...any insight? Would there be a reason to be scared of changing out the fluid? I bought the car from a family friend who had purchased it in 2008 with 28k on it, so they only put about 8k on it in 8 years. Female driver at that time who was really easy on the car and never drove it outside of town. Any thoughts/suggestions would be appreciated, just trying to preserve the transmission while not breaking the bank. The car is my "fun" vehicle and not my daily driver. Thank you!!
-Logan

 

I have some of the same issues, even after changing filter and two drain/refills with Mercon SP. The next step is to take to a Jag specialist (not dealer) and have him do software updates and reset tcm with factory software.


Several other members have done that and report problem fixed.

 

I would say the same, start with a "in depth" maintenance. Buy a new filter/pan, connector sleeve and Mercon SP (6 qt?). There are very cheap kits on eBay (search for 6HP26), or go with original ZF parts.

Unlock the refill plug first, drain the fluid, remove the pan, inspect the big magnets for metal shavings, pull the trigger lock, remove the connector sleeve, replace the sleeve, put the lock in place, put the pan back (use proper torque sequence for all (21?) bolts), and perform the ZF refill procedure (it's temperature-based, and needs to be followed to the letter). If you are going to do that yourself, there are great PDFs for this online.

Then drive around for a while. At a later point (3 months?), do a drain/refill to further dilute the old fluid that was left in the torque converter. This is where the cheap Mercon SP pays out nicely I suppose.

There are also 2 software procedures that can be done with the SDD factory software to smooth things out. There is the adaptation re-set (basically a test drive with instructions from the software) to re-calibrate the solenoid valves (this is followed by a 100 miles of said adaptation), then there is the reflash (replacing the code that runs in the TCM if it is not the newest). If you go down that road, do a reflash first to be at the latest code level, then have the same shop do the adaptations. This is not terribly complicated and does not take for ever, but expect to hit the min diagnostic fee of the dealer/shop, say, 1.5 hour labor.

Then you can go from there, too. Next would be some form of valve body refurb (pricey, but the transmission still remains on the car, so labor is not terrible) with a new bridge seal, etc.

Also, before spending big, keep in mind that modern transmissions work with external input, and those need to be checked out as well (think brake switch and ABS module).

Last, all of the rest of the drivetrain still counts: rubber coupling to the driveshaft, differential (oil), half shafts that need periodic grease, etc.

Best of luck, keep us posted.

 

Okay, so in summary: drop/replace the pan as well as the connector sleeve, replenish tranny oil, then follow up with a drain and fill after about 300 miles of driving. Oil being Mercon SP...is there only one type? Just want to make sure I am buying the right kind for my mechanic.

The adaptation rest that I am reading about...it sounds like I can do that myself by just driving the car through the cycle 5 times and do not need any dealer equipment...would my thinking be correct?

 

I think a reflash and loading of updates using dealer or indie software is way beyond the adaptation process. But I'm certainly interested in your experience.

 

Over the winter I removed the pan/filter, let it drip for about 2 full days and then installed a new pan and Mercon SP ( it took almost 8L ). I have noticed a remarkable improvement in shifting smoothness and overall performance of the transmission. The local dealer did not even exist in 2004 and knows nothing about any Jag model of that time; and the nearest Jag indy is well over 1000 km away on the mainland.

Can you folks with knowledge please elaborate a bit more on the adaptation re-set and the re-flash ? What would they accomplish ? I am currently quite happy with how the transmission performs but am a great believer in proactive maintenance on a 14 year old vehicle that is creeping up to 200,000 km

Thanks

 

Technical Service Bulletin JTB00145 describes the ZF Adaptation Drive Cycle reprogramming in step-by-step detail. When my wife began complaining of harsh shift issues in her 2006 XK8 at just over 67,000 miles back in July 2013, Rick (joycesjag) and I did a pan drop / new sleeve / ATF refresh using Lifeguard 6. I immediately followed that up by having the one Jaguar dealership I trust here in North Carolina (Jaguar Greensboro) perform the Adaptation Drive Cycle procedure for a negotiated price of $150. Jaguar Greensboro has two master techs who both have more than 30 years of Jaguar experience, so they know our generation of XK8s very well and have done this procedure many times during their careers. Part of my deal with the service manager was that these two master techs would be the only ones performing the procedure on my wife's car. This course of action completely cured her harsh shift issues until April 2016 at just over 101,000 miles when she began complaining of the same harsh shift issues again. So Rick, Wayne (cjd777), and I did an ATF drain-and-fill (no pan drop) using Mercon SP, and I immediately followed up by having Jaguar Greensboro do yet another Adaptive Drive Cycle procedure for the same $150 negotiated price. Again, her harsh shift issues were completely cured. Rick, Wayne, and I did one more Mercon SP drain-and-fill (no pan drop) about 7 months later in November 2016 at just over 106,000 miles just to ensure that the bulk of the ATF in her ZF was indeed Mercon SP. Now at 115,250 miles, I have had no complaints regarding harsh shift issues from her since....

If you opt to have the procedure performed on your car, ensure that the dealership or indie you select is very familiar with it and still has the necessary hardware/software to successfully complete it. You also want the two technicians involved in your procedure (one driving your car, the other working the laptop hooked up through your OBDII port) to be experienced in doing this procedure on previous vehicles. And to ensure that you get exactly what you want, be sure to print out a copy of JTB00145 and present it to the service manager when you hand over your keys. Review the steps with him, thereby setting your expectation up front. And be sure to talk with the techs after the procedure to verify that they indeed achieved a successful result....

 

I had the same issue with a severe first-to-second up-shift "hammer" when I bought my '05 (almost backed out of the purchase). Did a trans drain-and-refill twice with Mercon SP, plus re-flash and adaptation re-set (the re-flash cleared over 15,000 recorded adaptations from over the years). Hooray, no more problems in over 10,000 miles!

 

My understanding of the re-flash is that it replaces the code the transmission controller runs, similar to a major OS update on a mobile phone. Jaguar/ZF come up with software updates for whoever long after the transmission is put in service. That new code is downloaded to the transmission control module using the USB cable from a laptop running SDD. There is at least one post where someone performed this task with the BD kit (I have not), so it does not seem to be all that special. Boils down to whatever update is available on the SDD image you have access to. On the other hand, I very much doubt there are recent updates, I assume ZF is no longer producing updates for our cars. You have to keep in mind there there is always the possibility of botching this procedure (bad battery?) and end up with a non-functional TCM, so typically shops only perform this procedure when the transmission is in good working condition with no codes, etc. They do not want to be held responsible for a failed update. Did I mention you need a good battery for this? Or put the battery on a tender. The software has a big green/yellow/red indicator on the upper right corner to make sure...

For the adaptations, this is again a procedure run from the SDD software with the USB cable. It instruct the driver to drive the car at certain speeds on the open road and (gently) accelerate through the gears, one by one, while keeping the "bar" within a green zone. This has to do with the way the solenoid valves in the valve body are controlled: they are basically switches (fluid is allowed to flow through them or not depending on the voltage applied), but the control voltage can be modulated rapidly and effectively make the valve partially open, to a degree controlled by software. For some reason, this control cannot be calibrated entirely at the factory, and need to be made individually on each transmission for maximum shifting smoothness. For a variety of reasons linked to wear, these adaptations can become obsolete, and can (need?) to be re-set after all maintenance procedures (fluid changes, valve body work, etc.). Once the software procedures comes to a conclusion, it is followed by 100 miles of adaptations where the transmission "learns" to shift this particular unit as smoothly as it can. Then, after 100 miles, these adaptations are set. My superficial understanding is that executing this procedures introduces a bit of slip as it learns, which causes some clutch wear, so this is not something to run "all the time", so at every fluid change (30k or 50k miles?) is probably an upper limit (my assumption here).

Hope this helps.

 

Thanks for the replies. As I stated, our one and only local Jag dealer did not even exist in 2004. They have no knowledge of the XK8 ( or anything else pre-2010 ish ) They claim that they can't even read or clear codes for an XK8 ( I can with my phone ).........so they can't possibly work on the transmission. There is no Jaguar specialized indy shop for more than 1000 km ; so I guess I won't be having this procedure done btw. The car shifts like silk , but I just wanted to understand the process.

 

Contact eurotransspecialists.com in Los Angeles. They are very good.

 

LoL about 7000 km from me

 

Just verifying that there is only one Mercon SP out there (red bottle, Ford logo on it)???....it seems to be in scarce supply and I want to ensure I am buying the correct fluid.

Thanks!

 

That's the one; go for it. Could be one of two labels on it. (I have a case tucked away in the garage....)

 

Thanks! @Redline

 

wow, what a great bunch of info here - I am having some issues with my 03 XK8's trans as well - I can hear it slipping - would anyone happen to know of an independent mechanic that is familiar with these trans issues that is near me in Florham Park, NJ?