LR4 Transmission Calibration (adaption clearing) after service

[Land Rover Joe]

Tribe,

There is a lot of great information on this forum and others (as well as YouTube) for ZF transmission services (my 2010 LR4 has a ZF 6HP26, or the "six speed").

However, there is less available about the transmission calibration (i.e. resetting the adaptation values).

Does anyone have any experience, insight, or wisdom to clear the adaptation values on their ZF after a transmission service?

 

[Land Rover Joe]

Here are some useful references regarding this subject -

Websites:

3.6 TDv8 / ZF6HP26 Gearbox Oil Change available on - https://www.fullfatrr.com/forum/post551482.html#551482

ZF 6HP26 Gearbox Adaptions available on https://www.fullfatrr.com/forum/post584670.html

Calibration (adaption clearing) for Transmission after service? available on https://landroverforums.com/forum/l...on-clearing-transmission-after-service-95221/

Recalibrate gearbox available on - https://www.disco3.co.uk/forum/recalibrate-gearbox-200582.html

How To Reset & Relearn BMW E90 (E91, E92, E93) Automatic Transmission Adaptations (ZF 6-Speed) available on
https://www.fcpeuro.com/blog/how-to-reset-relearn-e90-bmw-automatic-transmission-adaptations-zf6

That website includes the “Relearn Procedures”; for an example, See software “N” - https://s3.amazonaws.com/fcp-creati...t_e90_transmission_adaptations/Software+N.png

You Tube Videos:

Land Rover LR3 Transmission Adaptation Relearn Procedure - Ep. 6 by Waffle Square available at

ZF 6HP Adaptations (Part 1) Diag.net (REVISED) by Diagnostic Network available at

How to reset and calibrate transmission adaptations on a ZF6 speed gearbox (BMW) by Ecologicaltime available at

 

[Land Rover Joe]

I reached out to the folks for my GAP Tool and they noted a couple things:

"I would be careful with the TCM adaption clear as there's a risk as per the user manual."

"Others can be done without a specific order. Of course, these are not required unless parts are replaced."

My understanding is that the ZF transmission needs to be cleared, which makes sense in terms of some of the issues I have with shifting (it is not that smooth).

However, the GAP folks note that the TCM clear should not be done - which is the transfer case. Conventional wisdom as the GAP Team notes, and I am not sure why, is that the transfer case should be left alone unless there are problems.

Again, looking for advice and insights before I start tinkering with the programming in the truck - probably starting with the transmission.

 

[greiswig]

FWIW I was told by the transmission shop who rebuilt my ZF, and who seem to know a lot about that tranny in particular, that it wasn't necessary. The computer would adapt to the new values within about 500 miles. This was also with the Zip Kit newly installed. They told me to treat it a little gingerly for the first 50 or so, then I could drive it like a scalded cat.

 

[Al Pizzica]

Also, no data just reading forums, seems as though people who clear the ZF adaptation later in transmission life have more problems than those who don't.

 

[powershift]

FWIW I was told by the transmission shop who rebuilt my ZF, and who seem to know a lot about that tranny in particular, that it wasn't necessary. The computer would adapt to the new values within about 500 miles. This was also with the Zip Kit newly installed. They told me to treat it a little gingerly for the first 50 or so, then I could drive it like a scalded cat.

Sounds like a good shop. I've come to like the 6sp, but would like to control shifting more in S mode or at least learn when it is going to shift. At WOT its predictable, but I like to keep the shifts further under redline. I don't need all that power sometimes and just enough is all that is really needed so that I can save the tranny. All my manuals needed was clutch parts and if the clutch wasn't slipping and working it was good to beat on daily all day long except when cold. With an auto I'm not sure lol.

 

[Land Rover Joe]

Tribe,

I wanted to follow up with this thread and where I ended up with resetting the transmission values.

BLUF: I didn't.

I wanted to see how things went after several weeks of running the truck (in generally slow stop-and-go traffic) and then with my shake-down test drive which included both high-speed, highway driving as well off-road driving.

For a flavor of Engine Temperature Readings:

75 mph. Ambient 24 C. Highway.
Sump (Sensor) - 199 F
Coolant (Sensor) 1 - 188 F
Coolant (Sensor) 2 - 140 F

75 mph. Ambient 24 C. Highway.
Sump - 197 F
Coolant 1 - 185 F
Coolant 2 - 147 F

25 mph. Ambient 26 C. After highway and then during city driving.
Sump - 203 F
Coolant 1 - 201 F
Coolant 2 - 189 F

0 mph. Ambient 26 C. After highway and then after driving in city.
Sump - 208 F
Coolant 1 - 199 F
Coolant 2 - 180 F

One can see that engine temperatures were really low on the highway and then spiked after coming into town after the high speed highway driving. I assume that is because ambient temperatures were low and the high speed really allowed the radiator to keep the coolant temperatures down (that is my own guess).

Shifting was very smooth (more on that later) and no issues. Basically, there was no reason to reset the values (so the collective seems to have been right to just let the transmission naturally feel its way over time).

But then I noticed something else interesting which I didn't know.

15 mph at 1500. Ambient 25 C. High Range, off road program, off road height.
Sump - 216 F
Coolant 1 - 208 F
Coolant 2 - 199 F
Transmission - 217 F

Off roading brought engine temperature up quite a bit. But I started watching the transmission temperatures and they would exceed 230 while the sump temperature would normally be a lot lower, usually around 200-210. Basically, the transmission fluid is always running hot with the various engine temperatures go up and down a lot.

I suppose folks who know things already knew this so nothing I have truly discovered here but this goes to the point about changing transmission fluid and filters (on a number of separate threads): it gets hot in there.

 

[Land Rover Joe]

Back to the transmission reset values.

Watching the shifting and other rates over a whole range of driving conditions made me realize that the issue that I had thought was poor shifting is probably something closer to throttle controls. The annoying thing that has been bothering me for a long time is rough running and a kind of jumping at low speeds while the engine is under load (like climbing a hill in High Range and low speed). There is this sluggish power and then jumping which I assumed it was a bit of sloppy shifting in the low gears. I now think (and I have the V8 5.0L) that this is a result of the higher torque V8 with the 6 speed which struggles to smoothly apply throttle controls (fuel injection and such) at low rpm and higher torques. Thus, when you hit the gas (even smoothly), you get a sudden surge of power when the controls catch up with the inputs - almost an over compensation.

I don't know any of this with certainty, just what i am guessing based upon my observations so I certainly welcome others experiences and insights.

So to make the now-long story short: shifting was not the issue (and therefore no need to reset transmission adaptive values and such). Throttle control and power applications for the V8 are my new suspect. Nothing super serious here - just the incessant quest for improving performance and driving.

 

[powershift]

The transmission could use a stronger cooler. Been thinking about adding one because I off-road when its hot asf, 46+ C. Lots of slow speed crawling, lots of forward, reverse and maneuvering. Sand mode turns the coolant fan on sooner but that wouldn't help the tranny probably unless the trans cooler is in the path of the radiator.

 

[Land Rover Joe]

The transmission could use a stronger cooler. Been thinking about adding one because I off-road when its hot asf, 46+ C. Lots of slow speed crawling, lots of forward, reverse and maneuvering. Sand mode turns the coolant fan on sooner but that wouldn't help the tranny probably unless the trans cooler is in the path of the radiator.

@powershift : You are absolutely correct: That is one of those odd things on this truck. I have been thinking the same thing - that a robust intercooler, maybe one just dedicated to the transmission with its own electric motor/pump, would be an improvement. Right now, the transmission intercooler, interchange, or heat-sink is at the very bottom of the (already too big and complicated) cooling system with a bunch of pipes that wind around for no reason I have yet been able to divine. I frankly don't understand the engineering with this and feel the transmission cooling system could be better designed. Granted, the cooling system from the factory is supposed to both warm up the transmission fluid/oil at start as well as help cool it at temperature...and the transmission is just going to run hot in there by the nature of the thing (back to the comment about fluid changes, particularly @bbyer 's recent note on a separate thread - I can't agree more) . But for the life of me, looking at the design drawings of the whole thing makes one wonder what was going on in the drafting room in Solihul (of course, not actually where the engineers work and no one is using pen-and-paper anymore)...

So yes - for those intrepid folks out there a larger / better cooling and pipe system for the transmission seems that it might help keep temperatures down and therefore (I assume) extend the life of the thing. Perhaps someone has tried this with an LR3 or LR4 already?