Last week I had my 6hP26 gearbox serviced (s type 3.0l 2004 139,000 miles). Basically a complete drain, new sump and seals etc.
We used the Launch 501 exchanger connected to the oil cooler pipes. 15 litres of lifeguard 6 in total.
Old fluid didn't have any burnt smell. Didn't see any shiny particles on the old sump.

Unfortunately the garage weren't able to reset the adaptions or perform any software upgrade.

Been having issues with lumpy changes, rpm surge 40-60 mph while cruising, and the occassionaly gearbox fault when putting it into reverse which goes away after restarting.

Some of you may know from my thread on another forum already.

Anyway its now in with VMTP Midlands ZF specialist. Tomorrow on Monday they will look at it.
I am praying and praying that its the just the incorrect oil level and needs the tcm adaptions reset etc.

Of course the gearbox specialists were full of doom and gloom about it having worn bushes and will probably need a rebuild even before looking at it.

I've asked them to first check the oil, reset adaptions, software upgrades (one for the surge also), and drive cycle.
Just hoping no faults come up for the mechatronic unit.

Thanks

 

I'm quite sure that either you have incorrect oil level or the TCM is making problems. It has to be measured at exactly 30 degrees Celsius. Also you have to reset the TCU after an oil change. That's just my 50 cents of experience driving and servicing those gearboxes in quite a few cars that I own.

 

Is the MIL on? If so, what DTCs are stored?

If the engine has misfire(s) occurring, the TCM will post the message on the instrument cluster stating 'Gearbox Fault'.

 

I bought my car with 120k mi. on the odo. with no proof the trans had ever been serviced. I've never had a problem in the 15k I've added. The only time I ever noticed the dreaded "clunk" was a few times on cruise control where it would down shift smoothly on a hill but have a slight clunk when shifting back into a higher gear. I have an iCarsoft and check the trans temp on a 3hr drive @ 70-80mph and the temp doesn't go over 75C (167F) that is well below the 200F operating temp of the 6HP26 that makes me continue to feel like I don't want anyone messing with it for the fear of this..

 

That does sound like an awful lot of Trans fluid... I fully serviced mine and it took a litle over 9 litres. Im not sure how much is in the cooler pipes and unit but an additional 6 litres seems way to much. Overfilling these boxes will cause lumpy changes I believe...

 

The machines use the extra 6 odd litres to 'flush' through and get out as much of the old fluid as possible. There's been huuuge debate about using these machines on the UK site very recently, with some lengthy threads..

 

Wow, 6L at $60 a litre (here that's what I paid) is a masssive extra cost. I don't really see the gain. Do you flush the engine out with clean oil before refilling it after a service?

 

Wow, that's even more expensive than here !

I don't do engine flushes myself, I just change regularly. It's not the same thing with the gearbox & torque converter though, as I've come to understand from following the threads I mentioned. Apparently quite a bit of the old oil is supposed to remain behind & the machine is supposed to change more of it. I just have my indie do my gearbox services, (3rd one done less than 10k ago), & all seems fine, along with everyone else who does it the 'usual' way.

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There are miles of threads about Mercon SP.

https://www.jaguarforums.com/forum/x...p-6hp26-84965/

 

Yep, same over here. Many, many posts & some huge threads/debate about alternative oils for the zf 6hp26 gearbox.

 

Actually according to ZF it is 40 degrees Celsius and you do not have to reset the TCU after a fluid change.

When I flushed my ZF6HP26 myself, with wife's help, using the trans cooler lines a quart at a time until the fluid was clear doing a fill check at approx 40 degrees C.
I used a little over 10 quarts. After a test drive I checked the fluid level at 40 degrees C and it required a little more to "top off".

 

Another vote to properly check the fluid level first.
Sounds like a good flush was done but I don't see where the level was even checked??
Any idea how is was set?

Please post back what you find out.
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Fluid level check is critical.

The temperature at which it is done will dictate whether it is under-filled or overfilled or properly filled.

Also the trans has to be "level".