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Discussion Starter #41
Thanks for the update! So I timed the 0-100 Kph on the video (unscientifically) and got 6.25 seconds.......awesome!
The only "scientific" run I have was with a GPS app, and I got 6.9s and that was before the TCM changes, so i expect a tenth or two off with just raising the shift points. I should be able to get to 60mph with only having the 1-2 shift instead of getting into 3rd just before 60mph. However i'm running my 30.5" tires so once I go back to my 29" tires I might still hit 3rd before 60mph.
 

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Discussion Starter #42
Another update!

First off I want to thank Chris Zelinsky from www.player3.ca for working on this TCM tune. He can take the credit as the first person to Tune a ZF9. Tuning for ZF8's have been out for a while and while you would think they are similar the process is much more involved, but hats off to Chris for doing a fantastic job.

My requests were

Only deal with Sport mode, leave all other modes with factory values.
Raise RPM slightly for gear shifts and firm up some of the shifts.

Without driving the vehicle its hard to convey how great the results are. Downshifts are nearly instant shifts are firm just exactly how I wanted them.

This video shows how quick the downshifts are in sport mode from a roll


Only had time to make 1 video showing the shift points but it shifts hard and quick.


I'm a very happy camper right now>:D
 

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I signed up on this forum just to follow your tuning progress. My wife loves her 2015 Cherokee but, admittedly, the V6 and 9-speed combo is a bit lacking. She is on the fence about trading it in on a Grand Cherokee as they seem to have better programming (at least from our test drive). However, should this be solvable via transmission and/or engine programming, she would happily keep the Cherokee. She is looking for more responsiveness in day-to-day driving. The sport mode goes a bit overboard on aggressiveness keeping RPMs too high. Throttle and shift responsiveness is worlds better than the normal mode, though. Maybe splitting the difference between the 2 would be perfect.
 

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Discussion Starter #45
I signed up on this forum just to follow your tuning progress. My wife loves her 2015 Cherokee but, admittedly, the V6 and 9-speed combo is a bit lacking. She is on the fence about trading it in on a Grand Cherokee as they seem to have better programming (at least from our test drive). However, should this be solvable via transmission and/or engine programming, she would happily keep the Cherokee. She is looking for more responsiveness in day-to-day driving. The sport mode goes a bit overboard on aggressiveness keeping RPMs too high. Throttle and shift responsiveness is worlds better than the normal mode, though. Maybe splitting the difference between the 2 would be perfect.
You absolutely could do a trans tune, the thing is its not a super easy process (but not as difficult as the PCM tuning as the TCM is UNLOCKED) Right now literally the gentleman as Player 3 myself and 1 other person are working on the TCM tunes so its still in its infancy. How mechanically/computer inclined are you? I'm not saying you shouldn't do it but it does take some time and cost some money although it would be cheaper than buying a different vehicle
 

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You absolutely could do a trans tune, the thing is its not a super easy process (but not as difficult as the PCM tuning as the TCM is UNLOCKED) Right now literally the gentleman as Player 3 myself and 1 other person are working on the TCM tunes so its still in its infancy. How mechanically/computer inclined are you? I'm not saying you shouldn't do it but it does take some time and cost some money although it would be cheaper than buying a different vehicle
I am fairly mechanically/computer inclined but I am more looking to find someone to do the tuning for me than do it myself. Considering the alternative is buying a new car, I am certainly willing to throw some money at it. Unlike the PCM tuning thread, I didn't see you mention what is really needed, equipment-wise, to tune the TCM.
 

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Discussion Starter #47
I will make a separate post on how to but its similar to the PCM tuning.

1. Buy HP Tuners MPVI2

https://www.hptuners.com/mpvi2/

2. Buy 4 universal credits

3. Read TCM with Windows based computer and MPV2

4. Send TCM file off to www.player3.ca

5. Player 3 will send you a modified TCM back

6. Load TCM and Data log with HP tuners software.

7. Send logs back to Player3 with comments on changes/adjustments if needed.

8. Enjoy!
 

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Discussion Starter #48
One of the benefits of having a TCM tune done.
Acceleration from a roll is much better as the vehicle will downshift to a lower gear than it did before.
Before: (Auto Mode)
This is a 7th-3rd Gear shift
After(Tuned) (Sport mode)
This is a 4th-2nd gear shift. Previously It wouldn't shift in to 2nd gear at this speed regardless of selec terrain mode. Allows the Pentastar to get into the higher RPMS where it likes to make power.
 

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Very Impressive Tyler. I also own a 2016 granite Trailhawk that I have already put on 42,000 KM with. I did receive 1 transmission Flash as that was the mandatory flash from 2017.

I am not happy with the default sport mode. First off it revives way to high and hold on to that rev to long going from 1st-2nd. Did you have this experience with yours before programming.
 

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Discussion Starter #50
Very Impressive Tyler. I also own a 2016 granite Trailhawk that I have already put on 42,000 KM with. I did receive 1 transmission Flash as that was the mandatory flash from 2017.

I am not happy with the default sport mode. First off it revives way to high and hold on to that rev to long going from 1st-2nd. Did you have this experience with yours before programming.
Sport mode is designed to shift exactly like that.


its programmed to hold all gears much longer regardless of throttle position
 

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I had to laugh, as I’m watching the video on July 1 and seeing the -39 C as your outside temp the day you shot the video! You clearly had the engine warmed up!
 

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Sport mode is designed to shift exactly like that.

http://www.youtube.com/watch?v=OwxgEc3GDUw

its programmed to hold all gears much longer regardless of throttle position
Sorry for the late response Tyler, as I have been away for almost moth. Regarding your response, I am aware that sport mode will hold on to the rev much longer, thus morphing the car into a 6-7 speed shifter. The issue is 1st and 2nd gear are revving way to high and to long compared to the other gears. Is there a way to only alter the shifting behavior of the first 2 gears. You will prematurely wear or damage the pentastar if you use it in sport sport mode for your everyday city stop/go driving. Pentastar engines are notorious for blowing head gaskets, just ask the police force. See they push those engines hard(high rev's) and I see no need for 1st and 2nd to rev high when they already cause the car to accelerate fast due to the gear ratio.

I just hate the elastically CVT behavior the ZF-9 exhibits when ever the vehicle must downshift for immediate pickup. Sport mode is the only cure to this problem and when ever I am driving on the freeway and have to revert back to normal mode it's incredibly annoying. The problem is due to traffic you are always having to brake, thus lose speed and when you need to pick speed up again, long delays while the Dog clutch on 5th has to sync both ends of the teeth which is what causes that delay in the transmission. Most describe it as a rubber band feel cause they are pressing on the Fly by Wire throttle harder while hardly anything happens only to have the car jolt after a 1-2 sec delay when 5th finally engages.

It's a shame really, cause ZF is literally the most respected Transmission designer/manufacturer in the world. They consider the 9 speed to be the black sheep of the family. The grand Cherokee Summit Eco Diesel I drove before was a dream when shifting since it used the world renowned ZF-8 which is only for Longitudinal mounted Engines.

Aside from the Transmission being the weakest point of the vehicle, I am very happy with it. I have haven't had any breakdowns, electrical glitches etc... Plus the actual Alfa Platform that the Cherokee was built and modified on has excellent handling and mannerisms(much better than the competition when I was shopping) which shouldn't be of any surprise since Alfa Romeo has always excelled in that department.

Based on your experience with the minor tunes to the transmission how feasible would it be to only modify the first two gears.
 

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Discussion Starter #53
1st-2nd shifting at other than full throttle shifts higher, but not enough to damage the engine. I get police service is harsh use (most of my family is in law enforcement) but the general public has not had lots of issues with Pentastar engines blowing head gaskets. Lots of forced induction Pentastar engines without head gasket issues.

Sport mode is designed to hold gears longer for "sportier driving" its not hurting the vehicle at all


The above video was done with very light throttle to show the higher shift points.

In terms of it feeling like a CVT i've never experienced that in any of the cherokees i've driven or tuned.

I really haven't had any of the issues you describe at all even with the dog clutch shifts.


This is a shift involving the dog clutch, no problems


If you are only looking to lower the rpm between the 1-2 shift in sport mode I would think around $700 would be pretty expensive for a rather small change.
 
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