[Jonesy76]

Hi all
I've recently had a gearbox service on my bmw 435d xdrive it's a 17 plate and done 80,000 before the gearbox service it was perfectly fine , last week I had the oil change and the new pan with filter changed since then i've noticed when cold it hangs onto gear changes longer and also sometimes very hesitant to change and when warm sometimes does the same also felt if missed gears when put foot down and been hesitant to change now and then not all the time . If I'm honest it feels worse after I've had the service done . It was done at a bmw specialist using all genuine oil etc its also had the adaptions done .

[TurboWeasel]

Adaptations reset you mean? How many miles covered since the fluid/filter change? It can take 500-600 miles to relearn after resetting the adaptations.

It shouldn't be worse in any case. I noticed no difference at all after mine had it's first service done at 58K, but the mechanic did say the fluid that came out was still green, so it's clearly led an easy life.

[Jonesy76]

I've not even covered 200 mile mate so hopefully your right I'll just it time cheers

[TurboWeasel]

If no improvement after 500 or so miles, take it back and get them to check they put the correct amount of fluid in.

[555GGM]

Mine felt instantly better. I wouldn't wait 500 miles to take it back to be looked at. That's a lot of gear changes on a box that could be low on oil....

[Ennoch]

I thought adaptations weren't meant to be reset unless work has actually been done on the box internals?

[danb1979]

Originally Posted by Ennoch

I thought adaptations weren't meant to be reset unless work has actually been done on the box internals?

This is what Grant has said at Automatic Transmissions in Preston (ZF specialist also)

There's lots of mixed info re this online; so not sure what to make of it. But when I get my box serviced end of this month; I'll just continue driving it as I do

The XHP map will change it anyway

[TurboWeasel]

ISTA itself says "the adaptations can be reset if the customer reports drivability issues", so that isn't a hard no.

Adapt means change, and change they do, frequently. Monitor them week to week to see for yourself.

I've also read people saying they shouldn't be reset, but without a reason given. All the adaptations do is trim the clutch fill pressures to get the rpm difference between input and output shafts as small as possible. It's far from a complicated gearbox, and as already said, other car brands using the 8HP reset the adaptations during the service.

[Techno 9000]

I'll paste this here, from the people who make the XHP tool for adapting the ZF gearbox maps.

"Adaptions basically have two purposes. The very first is to overlay the basic maps, stored in the TCU, by some small offset maps to compensate mechanical/hydraulical tolerances. No transmission is 100% identical to the other in real life and those differences need to be kept in check. So, the aim is to correct the errors in the stored basic setting, if you will.

Secondly, every moving part inside the transmission will wear over it’s lifetime. This is especially true for the clutch packs, which are built to wear by nature. Just like your brake discs wear through friction between disc and pads, so do your clutches (there are 5 of them in the 6HP + the Torque Converter Clutch) on every shift. Don’t panic, most of that wear is controlled through the lubrication with the transmissions oil. That also explains, why oil changes approx. every 60.000 miles are not the worst idea, despite BMW not recommending them. Normally the 6HP’s clutches are good for 200.000 miles and much more. Wear of clutch packs means, they get thinner and thinner over their lifetime.

This leads to the conclusion, the transmission controller has to have a function, to compensate this. Those are the Quickcharge Times and Quickcharge Pressures. They are there to compensate the higher travel, the piston needs to actuate the clutch, before it starts to bite. This is the same principle, employed by your brake system and employed by a manual clutch to compensate for wear. It’s more complicated in the transmission, but the logic is the same.

So, with that knowledge, what is it good for to reset adaptions regularly? Simple answer: For nothing. In rare cases, on transmissions with already very high positive adaptions, this can even lead to a situation, where your transmission will refuse to shift and you basically have to rebuild it, before it will work again. And that is the reason, why adaptions do not get reset by the dealer on service work. There is no reasons for it, unless hardware on the transmission has been changed."

[dholdi2]

Originally Posted by Ennoch

I thought adaptations weren't meant to be reset unless work has actually been done on the box internals?

This was my understanding too when doing research before doing my oil change.
I didnt reset the adaptations, just changed the oil & pan following the ZF leaflet included with the kit.

[TurboWeasel]

Originally Posted by Techno 9000

I'll paste this here, from the people who make the XHP tool for adapting the ZF gearbox maps.

"Adaptions basically have two purposes. The very first is to overlay the basic maps, stored in the TCU, by some small offset maps to compensate mechanical/hydraulical tolerances. No transmission is 100% identical to the other in real life and those differences need to be kept in check. So, the aim is to correct the errors in the stored basic setting, if you will.

Secondly, every moving part inside the transmission will wear over it’s lifetime. This is especially true for the clutch packs, which are built to wear by nature. Just like your brake discs wear through friction between disc and pads, so do your clutches (there are 5 of them in the 6HP + the Torque Converter Clutch) on every shift. Don’t panic, most of that wear is controlled through the lubrication with the transmissions oil. That also explains, why oil changes approx. every 60.000 miles are not the worst idea, despite BMW not recommending them. Normally the 6HP’s clutches are good for 200.000 miles and much more. Wear of clutch packs means, they get thinner and thinner over their lifetime.

This leads to the conclusion, the transmission controller has to have a function, to compensate this. Those are the Quickcharge Times and Quickcharge Pressures. They are there to compensate the higher travel, the piston needs to actuate the clutch, before it starts to bite. This is the same principle, employed by your brake system and employed by a manual clutch to compensate for wear. It’s more complicated in the transmission, but the logic is the same.

So, with that knowledge, what is it good for to reset adaptions regularly? Simple answer: For nothing. In rare cases, on transmissions with already very high positive adaptions, this can even lead to a situation, where your transmission will refuse to shift and you basically have to rebuild it, before it will work again. And that is the reason, why adaptions do not get reset by the dealer on service work. There is no reasons for it, unless hardware on the transmission has been changed."

Yeah I read that myself some time ago.

It's a lot of waffle to essentially say - if your clutch fill pressures are at the 700mbar outer wear limit, then you may get shifting problems if you reset the adaptations, in rare cases.

He's also saying is it worth doing regularly? No. And I agree with that.

I wasn't suggesting reset them every week. Check them semi-regularly, sure, just to keep an eye on them as they are a good sign of clutch wear.

It's perfectly fine/normal to do it after a service. That's once every 5 years/60K miles. As I say, JLR cars do it. It's not just BMW and xHP that know how ZF gearboxes work.

It's also fine to do it after an xHP flash as well, since it will change all the adaptations anyway as the shift speeds are faster. Not only that, once the trans fluid hits 50 deg, the adaptation mapping kicks in and will change around a lot until the shifts stabilise....on every journey.

And he's referring to the 6HP. We don't have that gearbox in the F3x.

My adaptations are in the 20-70mbar and 8-20ms range, so there is no harm in resetting them what so ever. I did it purely to restart the learning cycle after the xHP flash.

It's exactly the same concept as short and long term fuel trims. If you understand what adaptations are, it's not an issue resetting them.

If people aren't comfortable resetting them, then don't do it. Simple as.

[dholdi2]

Originally Posted by TurboWeasel

Check them semi-regularly, sure, just to keep an eye on them as they are a good sign of clutch wear.

I'm guessing this will be done in ISTA.
Will have to have a play around and see if I can find it unless you can point me to it ?

[TurboWeasel]

Originally Posted by dholdi2

I'm guessing this will be done in ISTA.
Will have to have a play around and see if I can find it unless you can point me to it ?

Yeah ISTA or the xHP phone app can give you the readings as well under "View Diagnostics". I would have mentioned that previously but I only discovered it myself the other day.

To read the current values I would use the xHP app as ISTA is dog slow and clunky, but if you want to use it the adaptions are under - Vehicle Management > Service Function > Power Train > Transmission Control > Adjustment > Display and Reset Adaptations > Next > Display Adaptation Values.

xHP can't reset them though. For that you definitely will need ISTA.

Adaptation Limits:

Don't be alarmed if a couple of the clutches are at or close to the limit, it doesn't necessarily mean the clutch pack(s) is worn out. It could just need a simple fluid service at best, or a mechatronic solenoid and seal refresh at worst. ZF do a kit for the latter.

Common to most slush box autos, the long tube seals that seal the mechatronic valve body to the gearbox casing are known to shrink and harden with age, which can cause oil pressure bleeding, which will slow down the clutch fill time.

xHP are right in saying it's probably best not to reset adaptations on gearboxes close to or at the adaption limit because it might not have enough adjustment scope to recover again. If the adaptations are still big after a basic service, it's probably time for the mechatronics refresh kit.

And after that, if they are still big, it's new clutches time unfortunately. Generally only abused cars reach that stage.

Fill times are slower for D & E as they are the furthest from the oil pump, which is normal.

[Jonesy76]

Update on gearbox service after having car back for over a week I could notice the difference in the gear changes they were super smooth but every now and then it felt like 1st to 2nd was harsh and holding especially when driven hard and would get drivetrain error . I scanned car as it happend a few times and the error code stored was

420441 clutch E not plausible
2AF800 gearbox control unit

This has only happend after gearbox service , it is now in for the 3rd time.when it went in the 2nd time they said the fluid was a little low but they sorted out but when I had it back was still getting these errors and still getting drivetrain error so just hoping they can sort problem out .

[Eddamoo]

If they admit it's 'a little low' that suggests that they didn't follow the instructions by either:
1. Filling the trans when it's too hot. As it cools the fluid will become more dense. Maybe upto 100ml if the trans was very hot
2. They did the final fill without the engine/tc running meaning 1L+ was missing.

[TurboWeasel]

Clutch E is the furthest from the oil pump, so is the first to complain about oil pressure issues.

As above, it would need to be at least a litre under filled to start causing problems like this.

If topping it off doesn't fix the issue, they will need to drop the oil pan again and check things over. For example, make sure the O ring on the filter didn't get pinched and isn't a loose fit etc etc.

[Jonesy76]

Thanks for the information lads very much appreciated ill keep ya posted on the outcome just hope they fix it .

[Jonesy76]

Update on gearbox clutch E and drive train fault etc I pick the car back up today and I've been told they have put a new genuine pan on it and put fresh oil in again and told to drive it normally till it adjusts so see how it goes now sure how this would of caused the problem but let's see fingers crossed this time .

[TurboWeasel]

This is probably why BMW don't service them

Genuine pan eh? I didn't think BMW sold them, but what did you use before, the ZF aftermarket kit?

It's just a hunch, but I've seen on the older ZF 6HP aftermarket pans had an O ring that was too small for the valve block, so not enough fluid was being drawn in by the pump.
Could have been the same issue with yours but genuine stuff should sort it.

Does your code scanner show the transmission adaptations?

If it does, keep an eye on them.

Healthy numbers are around +/- 10 - 30ms for the 'rapid fill times' for Clutches A to E, and +/- 30 - 100mbar for the 'Clutch fill pressures', clutches A to E.

They are basically the adjustments needed to lock the clutches as commanded by the TCU. The smaller, the better.

If the fill pressures quickly start getting to 400+, I would take it back to them again.

[Jonesy76]

Just got car back new pan and oil done again and been told to driving it easy for a bit until everything is adjust,seems really smooth at the mo but don't not put foot down so we will see . Will adaption figures stay same or will they change ill get them on reader and post up hear for ya to see mate .

[BMW Fanboy]

Jonesy76: I note your location is "Chester" & your ZF service was done at a BMW Dealership. I always thought the BMW stance was that the unit was good for the life of the vehicle despite the advice by ZF to the contrary so it is good to see that a dealership will undertake such work. I am in Liverpool, have extended the warranty on my 2019 430i & will continue to do so for peace of mind. My vehicle is just under 11k (retired so limited use) so a gearbox service should be a while off yet. I use the Williams Dealership in Liverpool. Did you use Halliwell Jones Dealership in Chester?

[TurboWeasel]

Originally Posted by Jonesy76

Will adaption figures stay same or will they change ill get them on reader and post up hear for ya to see mate .

They will be all over the place for the first 100 miles or so and then will settle down. Post 13 shows the adaptation limits. Beyond those numbers the TCU no longer has precise control of the clutches and you can start getting bad shifts and gear hang, but hopefully that won't happen.

Do you mind sharing the cost of the BMW pan and oil? I'm thinking I might go genuine next time I do the service on mine for peace of mind.