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I have a 2016 Advance. Yesterday I had the cruise set at 60 mph and noticed the RPMs were the same as they are when the cruise is set on 75. Seemed weird. I pulled the "+" shift paddle behind the steering wheel and noticed the transmission was only in 8th gear instead of 9th. Once I pulled the paddle and shifted to 9th gear, the RPMs dropped down to about 1500. It seems that I have to be going about 65 mph for the transmission to automatically shift into 9th gear. Wouldn't I get better gas mileage if the transmission shifted to 9th at 60 mph? I drive on mostly flat terrain. Anybody else checked the RPMs at 60 mph? Wondering if everyone's is this way. Thanks.
 

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All you need to do is a search of ZF 9 speed and you will find that it is plagued with issues. You can check out the chrysler site, Honda , Fiat and land Rover. There have been 8-9 shift concerns rpm concerns which are blamed on the drivers driving habbits. Just say that one family member has a heavier foot than the other family member, great dinner disscussion, this they claim can cause issues as the transmission learns your driving habbits and adusts to them! You really need to have a read on the ZF transmission to appreciate all the tech involved in it that have drivers questioning it!
 

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Jesus, Wilson, if I could slap you, I would.

People need to stop blaming the ZF9 for everything. Next thread I swear I’ll read how a ZF9 killed a baby and raped the mother.

This is not a fault. Ever drive a manual transmisssion? Lugging an engine is bad, mmmkay.

60mph just isn’t fast enough to require 9th gear.
 

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And just to point out:

The old Honda six speed auto had a 6th gear ratio of 0.56.

The ZF9HP48 ratio for 8th gear is 0.58.

So there ya go.
 

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can the 9 speed paddle shift when it is in drive? In the earlier gen 3 one is supposed to be in sequential shift mode to paddle shift.
 

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My misunderstanding, as I agree with your analogy . I thought "Mdxtsx" was implying that the car was not shifting into 9th gear as though he had experienced it doing so in the past at the speeds stated! Not Shifting into 9th gear has been one of the reported problems not related to rpm. I as many are not yet ready to give the ZF9 a passing grade by any stretch as it has had issues since conception and share of class action lawsuits. Many are watching Honda as Acura TLX and MDX owners are experiencing the same issues.
 

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can the 9 speed paddle shift when it is in drive? In the earlier gen 3 one is supposed to be in sequential shift mode to paddle shift.
yes, you can be in normal "D" and use the paddle shifters. I do it daily. It returns to a computer-selected gear relatively quickly, but it will honor down/up-shift requests. There is one particular hill where I'll downshift 3-4 gears right before I crest the apex.
 

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I think Sport + keeps you out of 9th, but maybe regular "Sport" raises the speed requirement for 9th. I don't really have any issues with my trans, and I'm in Comfort mode most of the time. I do like to play with Sport+ once in a while. Love the responsiveness.
 

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I think Sport + keeps you out of 9th, but maybe regular "Sport" raises the speed requirement for 9th. I don't really have any issues with my trans, and I'm in Comfort mode most of the time. I do like to play with Sport+ once in a while. Love the responsiveness.
I don't believe the MDX has "Sport+"... Only Comfort, Normal, and Sport.
 

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60 in my 2015, flat and level light load, on 3 cyl is about 1600 - 1700 RPM. Checked it last night. 9th might be waiting for a little more RPM.
 

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Keep in mind your engine can modulate between 3 and 6 cylinders. 9th gear in 3-cylinder mode is the most efficient possible combination, but imagine a scenario where you need more power because you are going uphill or into the wind or traveling faster and creating more wind resistance. Your computer has several choices as to how to deal with the problem. 1) Switch to 6 Cylinder mode. 2) Shift to 8th gear (or lower) 3) dump more fuel into the combustion chamber.

In theory, Honda engineers have spent hours pouring over data figuring out what to do in different scenarios. It's possible that in certain situations a manual override would squeeze out a little more fuel efficiency, but it's more likely that you will inadvertently lower your fuel efficiency by trying to monkey with it.

But honestly, I would tinker with it too... give a button to press and I'm going to press it!
 

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Wouldn't I get better gas mileage if the transmission shifted to 9th at 60 mph?
Not necessarily. There's a combination of variables at play and the overall mileage is affected by multiple of them including the RPM of the engine, the overall gear ratio, the 'lugging' of the engine when it's at too low of an RPM for the load, which is affected by the gear ratio, inclines (even very moderate ones), headwind, rolling resistance of the tires, the road surface, etc. along with a bit of a margin in order to have reasonable performance. Anyone who's driven a manual that has an overdrive is familiar with this combo of variables.
 

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Though I can’t prove it, I swear a software update was put through for my transmission a couple of months ago. During one service visit I asked about a squeal when decelerating around a corner and apply gas forcing a downshift. At some point after that I noticed my car began starting from a complete stop in second gear most of the time, and then also stopped shifting into 9th gear on its own at anything less than 63mph or so. You can force it into 9th gear as low as 56mph but unless you are on a relatively flat road it will go back to 8th under the slightest load. I do see a difference with the instant MPG when you get it into 9th, especially if it holds 3 cylinders.
 

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Does the 9 speed also have a lockup provision in the torque convertor? In and out of lock often feels like a gear change too in most cars.
 
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