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Discussion Starter #1 (Edited)
I'm going to make a separate through for this so it doesn't get lost in this tuning thread.

Doing some research on the ZF 9 Speed it appears that while the ECMS are locked on 2015+ Chrysler vehicles, the TCM (Transmission Computer) is NOT.

The issue is that should you want to edit (tune) the transmission it requires another 4 credits (on top of the 2 required for the ECM tuning)

Tonight I took the plunge and attempted to read my TCM and while it was successful the HP Tuners software did not recognize the file. This is not surprising since I don't think a single person on this planet has attempted to try and read this particular TCM.

Support ticket is open with HP Tuners and if it's anything like the last time I had issues they will have a solution for me within 24 hours.

Vehicle being read from is my 2016 TH

When I have some more time I'll try the read from my 2014.

Would be super interesting to see the differences in tuning between the 2 model years.





 

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Looking forward to seeing the results of this.
 

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I've been wondering why nobody has tried to re-tune this thing before. It needs it bad. Ha! I'm following, as well!
 

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Discussion Starter #5
I've been wondering why nobody has tried to re-tune this thing before. It needs it bad. Ha! I'm following, as well!
Still working with HP Tuners on this one, as I've got the beta software however no additional transmission programming options exist.

Nothing can ever be easy right?
 

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Could be interesting if 9th could be programed into the mix to function in normal driving and not labor the engine.
 

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Could be interesting if 9th could be programed into the mix to function in normal driving and not labor the engine.
We have a 9th?? I thought that was just a fairy tale! :)

I was cruising the freeway a couple of days ago. The cruise was set to 88 (75 MPH zone and I was being passed like crazy). I had the fuel economy gauge up so I could monitor instant MPG. Whenever I forced the transmission into 9th, the gauge would show a slight decrease. Pop the shifter back to the right and the transmission instantly went back to 8th and the fuel economy increased a bit. Did this several times on flat and slight downhill sections of the freeway. Never hit a scenario at 88 MPH where 9th actually helped MPG.

I know that's a very limited sample. I wonder just how fast one needs to go for 9th to be a help? It is clearly designed for the autobahn!
 

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We have a 9th?? I thought that was just a fairy tale! :)

I was cruising the freeway a couple of days ago. The cruise was set to 88 (75 MPH zone and I was being passed like crazy). I had the fuel economy gauge up so I could monitor instant MPG. Whenever I forced the transmission into 9th, the gauge would show a slight decrease. Pop the shifter back to the right and the transmission instantly went back to 8th and the fuel economy increased a bit. Did this several times on flat and slight downhill sections of the freeway. Never hit a scenario at 88 MPH where 9th actually helped MPG.

I know that's a very limited sample. I wonder just how fast one needs to go for 9th to be a help? It is clearly designed for the autobahn!
That's intriguing... When the 2.0T came out, with more torque down low and a shorter final drive ratio, I remember thinking that 9th would likely show up under 70 mph. Apparently not... I had also based my assumption on the fact that the 2.4 Tigershark KLs get into 9th quite readily below 75 mph. Hmmm. Guess I'd need an engineering degree to understand this one...
 

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I can shift into 9th anytime above 62 mph. But unless I’m running downhill and above 70 there is no mpg advantate over 8th; often there is a slight mpg disadvantage. Looking at the hp/tq curves for the 3.2 and the 2.0 the latter has a significant advantage below 2000 rpm.....but remember this is at WOT. At part throttle they would be much closer together Any boost added would kill mpg for the 2.0.


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Discussion Starter #12
I"m going to say this for the 100th time. If you have a V6 and NOT a 2019 don't lose sleep over the fact you don't get into 9th gear unless you are going at very high speeds. The vehicle isn't stupid its not going to go into a gear that lugs the engine which in turn makes it inefficient. Should there be a chance to attempt to program it in lower I would probably try but it's not at the front of my to-do list.

HP tuners got back to me again and it seems no one has ever read a ZF 9 speed transmission so they are creating a definition file on their end to facilitate being able to tune this transmission
 

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That is pretty impressive HP Tuners is going through all this work to help you out.
 

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Discussion Starter #14
Another update sadly not a good one. As per HP Tuners at this point in time there is no support to tune the ZF 9 Speed transmission. The next official release of their software should have this support. Patiently waiting.
 

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Could be interesting if 9th could be programed into the mix to function in normal driving and not labor the engine.
Unfortunately changing the programming will not change the gear ratio of the transmission.
 

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2019 TH and I am aware of the different software and the issues that 14-18 cherokees have, but if you can get a copy of the 2019 transmission software I would recommend it because the shifts are smooth, and it will kick down (at least in sport mode)
 

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Another update sadly not a good one. As per HP Tuners at this point in time there is no support to tune the ZF 9 Speed transmission. The next official release of their software should have this support. Patiently waiting.
Thanks for the update. Guess we wait.
 

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2019 TH and I am aware of the different software and the issues that 14-18 cherokees have, but if you can get a copy of the 2019 transmission software I would recommend it because the shifts are smooth, and it will kick down (at least in sport mode)
That might work for the 3.2L TCU as the part numbers are the same between 2018 and 2019 (MOPAR 68294441AA). The 2018 2.4L uses the same P/N TCU but I couldn't locate a P/N for the 2019 2.4L - it's probably the same.

However, according to RockAuto the 2.0L Turbo has a different P/N for the TCU (MOPAR 155250766). The pictures of the 2019 2.0L Turbo TCU are completely different from the others. The rebuild kits are different P/Ns for the 2.0L T as well. Looks like it's not quite the same animal as the 2.4L/3.2L 2019 or prior years.
 

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Discussion Starter #20
That might work for the 3.2L TCU as the part numbers are the same between 2018 and 2019 (MOPAR 68294441AA). The 2018 2.4L uses the same P/N TCU but I couldn't locate a P/N for the 2019 2.4L - it's probably the same.

However, according to RockAuto the 2.0L Turbo has a different P/N for the TCU (MOPAR 155250766). The pictures of the 2019 2.0L Turbo TCU are completely different from the others. The rebuild kits are different P/Ns for the 2.0L T as well. Looks like it's not quite the same animal as the 2.4L/3.2L 2019 or prior years.
Additionally 2018+ ECMS are more locked than previous years requiring a special cable to even read the ECM let alone tune it. Chrysler is making it extra hard to tune the newest vehicles
 
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