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Nagaman
1st May 2018, 12:57 PM
I don’t like transmissions that hunt around constantly.
Is the 9 speed so imperceptible that you don’t notice all the changes?.
What minimum speed gets you into 9th?.

Slunnie
1st May 2018, 05:12 PM
This recent article is interesting.
Ford decides against GM-built 9-speed automatic transmission - Autoblog (https://www.autoblog.com/2018/04/23/ford-gm-9-speed-automatic-transmission/)

SBD4
1st May 2018, 08:14 PM
Personal experience is the 9 speed is fine - just like the 8 speed in the larger vehicles. It doesn't hunt at all. The extra gears just means the car has a broader choice available to ensure optimal engine torque and power are available and for that reason would help to avoid hunting.

Nagaman
3rd May 2018, 07:25 AM
What speed do you have to reach before it goes into 9th?.

SBD4
3rd May 2018, 08:11 AM
What speed do you have to reach before it goes into 9th?.
I'll have to check. It's my wifes car so I won't have the opportunity until the weekend. Don't forget, the engine specs will also dictate when the gear changes will happen. Engines with lower torque/power output will be more likely to use the lower ratios more often.

Are you asking because you are looking to buy or do you have one already?

Nagaman
3rd May 2018, 08:59 AM
I'll have to check. It's my wifes car so I won't have the opportunity until the weekend. Don't forget, the engine specs will also dictate when the gear changes will happen. Engines with lower torque/power output will be more likely to use the lower ratios more often.

Are you asking because you are looking to buy or do you have one already?
I’m definitely in the market.......it’s just a matter of time and there is the update coming which makes it even more interesting. A higher info ‘screen’ would be an improvement from my perspective.

SBD4
3rd May 2018, 09:13 AM
I’m definitely in the market.......it’s just a matter of time and there is the update coming which makes it even more interesting. A higher info ‘screen’ would be an improvement from my perspective.
Excellent! What spec trim/engine are you aiming for?

Definitely be sure to get what you want. Too much money being spent to have regrets. Buying my RRS was a bit of a rush. Consequently there are things I missed out on that I really regret not having.

Nagaman
3rd May 2018, 07:17 PM
Excellent! What spec trim/engine are you aiming for?

Definitely be sure to get what you want. Too much money being spent to have regrets. Buying my RRS was a bit of a rush. Consequently there are things I missed out on that I really regret not having.
I’m looking to buy an SE and the basic diesel is fine . I don’t intend to get sucked into expensive options either.

justinc
3rd May 2018, 08:00 PM
More torque = no hunting around for gears😎

SBD4
5th May 2018, 02:49 PM
This information is probably a bit more like what you are looking for. You can see below that at 1000 RMP in 9th the car will be doing 72 KPH. when doing 100Kph the engine will be sitting at just under 1400RPM which it will do very comfortably (SD4 420nm/140Kw). As Justin said above, the more torque the more inclined the engine will be to use a higher ratio at a lower RPM:



Gearbox:
ZF 9HP48


Transmission type:
automatic



with CommandShift manual shift mode






Number of gears:
9


Gear ratios (overall):



I
4.7 (18.54)


II
2.84 (11.2)


III
1.91 (7.53)


IV
1.38 (5.44)


V
1 (3.94)


VI
0.81 (3.19)


VII
0.7 (2.76)


VIII
0.58 (2.29)


IX
0.48 (1.89)


X
()


R
3.81


Speed range



(max speed on gears,



top gear value theor.):
(km/h/mph)


I:
33 / 21


II:
55 / 34


III:
82 / 51


IV:
113 / 70


V:
156 / 97


VI:
192 / 119


VII:
223 / 139


VIII:
269 / 167


IX:
325 / 202


X:
/






1000rpm speed:
(km/h/mph)


I:
7.4 / 4.6


II:
12.2 / 7.6


III:
18.1 / 11.2


IV:
25.1 / 15.6


V:
34.6 / 21.5


VI:
42.7 / 26.5


VII:
49.5 / 30.8


VIII:
59.7 / 37.1


IX:
72.1 / 44.8


X:
/


Torque converter factor:



Final drive ratio std:
3.944

SBD4
5th May 2018, 06:53 PM
Actually, this is better: