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I have read a few times on this forum that the ZF9 shifts based on your driving habits, and did't really believe it. Below is an excerpt of an article I found. I found it interesting; but, for those that already know how it works, it may not be. And, I apologize, if this has been covered before.


"Frieder Mohr, an application engineer who’s worked with software and the internal controls for the nine-speed, said that the transmission goes through two levels of ‘adaptation’ to fine-tune its shift quality. One of those is as the transmission properly adjusts its shifts to internal tolerances, both when it’s new and as it wears. The second is adaptation to driving style, which takes just a few minutes and a few shifts through each gear.

Tips that the dealership probably won’t tell you

Mohr gave the following useful tips on how the nine-speed’s software works:

If you’re the gentler driver in the household, a few lumpy shifts are to be expected each time you get in after the more aggressive one. If one driver drives rapidly most or all the time, then it’s possible that the low-speed, low-load shifts won’t work so well, because the transmission will still be assuming the style of the more aggressive driver. It is possible that each time the gentler driver gets into the vehicle, the first few shifts may be firmer, but the software softens shift quality after just a few minutes of driving.
It’s actually important to mix driving styles when the vehicle is new. This is so that the transmission can ‘learn’ each shift over a range of conditions. The transmission could take longer to adapt if driven in a steady continuous way, but shifts should even then become smoother and more predictable over the long run.
That said, ZF isn’t willing to concede that all that we observe as odd drivability traits are related to their choices. When I asked about rough downshifts during a common American maneuver—a gentle rolling ‘stop’ followed by a right turn and moderate acceleration (one that’s a non-event in the Discovery Sport), Mohr deflected to FCA’s choices. “It sounds like what you’re describing there is related not to adaptation but to shift strategy, which is determined by our customer,” he said.

Land Rover Range Rover Evoque fitted with ZF 9HP nine-speed automatic transmissionLand Rover Range Rover Evoque fitted with ZF 9HP nine-speed automatic transmission
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Another engineer said that the supplier has found that Europeans expect partial-throttle downshifts on the highway in some cases—the nine-speed's apparent restlessness between eighth and ninth gear, in the four-cylinder Cherokee, for example—where Americans might judge it to be a flaw.

And that’s really the third component to this—the shift strategy itself. It’s the one aspect that’s not entirely under the ZF’s control, yet the supplier has likely learned a lesson that it should be more proactive.

You can be sure that other automakers are taking note. It might be time for automakers to wrap driving style into the keyfob profiles that are kept for a number of vehicles; that could be an easy remedy for this complexity. With more gears comes an even heavier burden on software and controls, and real-world tweaks.

Yet that hasn’t stopped several automakers—Ford and GM, for example—from working on ten-speeds. The more, the merrier."

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Thanks for posting. Some of this makes sense to me and the most notability for me is...

When I drive really gently, from a stop there is a kick at the beginning, like 1-2 not sure because I have a TH.

When I drive normal to aggressive, it is smooth all the the way thru the gears.

Overall I'm not worry as long as I'm not hearing any noises. I'll give the 9 speed a chance to learn my driving but I REALLY wish they would stop this leaning process and shift in a logical reprogrammed manner. My VW is 7 years old and all the shifts are smooth and predictable. No learning required!!!!
 

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"Frieder Mohr, an application engineer who’s worked with software and the internal controls for the nine-speed, said that the transmission goes through two levels of ‘adaptation’ to fine-tune its shift quality. One of those is as the transmission properly adjusts its shifts to internal tolerances, both when it’s new and as it wears. The second is adaptation to driving style, which takes just a few minutes and a few shifts through each gear.
I wish I knew what Mr Mohr means by tolerances. Tolerances are a design parameter that indicates how much a numerical value ( the actual size of something) may deviate from its intended value (the nominal size) and still be within spec. Tolerances do not change with wear. Clearances are the distances between moving parts, and they do increase with wear. Once a clearance has reached the limit set by the tolerance, a rebuild is in order. Not sure what's there to adjust for the transmission as it wears. The parts will be just increasingly looser.
 

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I never liked the idea of "learning" transmissions. I like my car to drive the same way every time I get in it. It's just another reason I don't like automatic transmissions.

My other car with its six speed manual transmission behaves exactly the same way every time I drive it. :D
 
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I never liked the idea of "learning" transmissions. I like my car to drive the same way every time I get in it. It's just another reason I don't like automatic transmissions.

My other car with its six speed manual transmission behaves exactly the same way every time I drive it. :D
I agree. Just shift already, slush box. Preferably in a predictable and repeatable manner.
 

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When I drive really gently, from a stop there is a kick at the beginning, like 1-2 not sure because I have a TH.
I thought the Renegade launches normally in 2nd? Anyway, the clunk may mean you are not stepping on it enough.

When I drive normal to aggressive, it is smooth all the the way thru the gears.
That means I should have very smooth shifting experience. >:D
 

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I thought the Renegade launches normally in 2nd? . . .
The Trailhawk normally starts in second. But if you put it to the floor, it will quickly shift into first and then shift through the gears normally.

I don't know about the other models with automatic transmission.
 
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