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Discussion Starter #21
After the 3rd Beta Software update, i'm still no farther ahead on being able to read the TCM file. Losing hope that this is going to actually get fixed because i'm the only person who's bugging HP Tuners for this support
 

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Discussion Starter #23
As far as I know, the only way to read and write data to a ZF is one of these.
ZF 8 Speeds have been read for quite a while now and lots of tuning available for them. They are quite widespread on popular dodge vehicles. The only reasons its not working out of the box is because no one has ever tried with HP Tuners like I have. HP Tuners is very receptive to getting it to work so in time I have faith they will get the definition files updated so it can be read properly. No different than when in 2015+ all the Chrysler vehicles had locked PCMs and not you can unlock them and tune them. Time and patience
 

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Discussion Starter #25
Not much to update as HP Tuners is still working on support for the 9 Speed. I've been playing around with ERS and found (not surprisingly) its a very unreliable method to attempt to get the vehicle to shift at a higher rpm.



You can see there is almost a 2 step rev limiter with a "soft' limiter at 6500rpm and then fuel cutoff at 6800.

Being tuned I no longer have the 6500rpm soft limiter issue and I can go right to 7000rpm the problem is that it's very abrupt and sounds bad.

The issue is no matter what rpm I tell ERS to go to the next higher gear it still ends up hitting off the rev limiter as there is most likely a bit of a delay between when you tell the ERS to upshift and when it actually happens, under WOT milliseconds count and get it wrong and your smash off the limiter like a riced out honda.

Based on how I have everything set up, a 6800rpm shifting RPM would probably work best.
 

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Not much to update as HP Tuners is still working on support for the 9 Speed. I've been playing around with ERS and found (not surprisingly) its a very unreliable method to attempt to get the vehicle to shift at a higher rpm.

You can see there is almost a 2 step rev limiter with a "soft' limiter at 6500rpm and then fuel cutoff at 6800.

Being tuned I no longer have the 6500rpm soft limiter issue and I can go right to 7000rpm the problem is that it's very abrupt and sounds bad.

The issue is no matter what rpm I tell ERS to go to the next higher gear it still ends up hitting off the rev limiter as there is most likely a bit of a delay between when you tell the ERS to upshift and when it actually happens, under WOT milliseconds count and get it wrong and your smash off the limiter like a riced out honda.

Based on how I have everything set up, a 6800rpm shifting RPM would probably work best.
I'm curious, have you tried to get the tranny to go into 9th gear more consistently?
 

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Discussion Starter #27
It won't go into 9th gear any more than it would otherwise. Its simply based on a bunch of variable and 99% of the time the reason is that the vehicle is not going fast enough to go into 9th gear. In Canada there is no place I could legally drive to get into 9th gear on regular basis. Fuel economy doesn't suffer because we don't see 9th gear very often. If you lived where you could drive 100mph all the time you would see 9th gear.
 

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It won't go into 9th gear any more than it would otherwise. Its simply based on a bunch of variable and 99% of the time the reason is that the vehicle is not going fast enough to go into 9th gear. In Canada there is no place I could legally drive to get into 9th gear on regular basis. Fuel economy doesn't suffer because we don't see 9th gear very often. If you lived where you could drive 100mph all the time you would see 9th gear.
My thought was, via programming, you might be able to reduce the speed at which 9th becomes available. Oh well, no matter. Was just curious.
 

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Honestly, I don't think you'll even get 9th gear even if you hit triple digit speeds simply because the amount of drag created would prevent the transmission from doing so. I could be slightly off on this, but at 100mph, I think the RPMs would be at or close to 2k RPMs in top gear, which I think is simply not enough to sustain that.

In my experience, 80-85mph (128-136kph) I can reach 9th gear more consistently, although I've only been able to do it when the road is completely flat, or at a slight downward angle. I doubt I'd be able to maintain that if I went 90-100mph, although I have yet to test it. I have done a triple digit run for a couple miles in the past, and was in 7th gear the whole time, but getting the car to accelerate at that speed might also cause that.

Keep in mind, I'm talking specifically about a stock Pentastar, so a modified one might result in a different conclusion.
 
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My experience so far with my '19 with the 2.0L Turbo is this...

1. Run up to speed (80 MPH or better).
2. Watch for police (75 MPH is max in AZ)
3. Put EVIC on MPG mode.
4. Force transmission into 9th gear (2019 has an AutoStick so it will go where you want it).
5. Watch instant MPG decrease.

I haven't found a speed where the transmission in 9th actually helps MPG, but I'll admit I having gone to "Autobahn" speeds yet (>85 MPH). I suspect the 9th-speed gears will remain quite shiny and un-worn throughout the life of the vehicle. :smile:
 

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Discussion Starter #31
Presenting the very FIRST 9 Speed transmission exposed via tuning! Yes you can now tune the ZF 9 Speed via HP Tuners. It took a long time but HP Tuners came through and worked with myself and another person (Brian Scott).

Now to go through and figure out was all this stuff means, there is an absolute TON of information to sort through.
What is going to be most interesting is the difference in programming between my 2014 and 2016 since they do shift different.

Here are some pictures














 

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Friggin' awesome! I'm very interested to see what they can do with this!
 

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This is such exciting news! Can't wait to see what will come of this. :D
 

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That is a lot of data! I too want to see what you can do with this. Keep us posted.
 

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Wow. I'd given up on the possibility of a smooth change from 2nd to 3rd or actually matching engine rpm to gearbox speed on downshifts (rather than the forward lurch).
Is it possible or will my hopes be dashed once more?

Crash486 - Jeep Cherokee Limited diesel
 

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Discussion Starter #36
Wow. I'd given up on the possibility of a smooth change from 2nd to 3rd or actually matching engine rpm to gearbox speed on downshifts (rather than the forward lurch).
Is it possible or will my hopes be dashed once more?

Crash486 - Jeep Cherokee Limited diesel
Since there is something like 89 different shift patterns its not cut and dried thats for sure

Maybe this is a value that needs to be changed for you




Also to note, i'm getting an error message reading my 2014 cherokee, it has a different operating system so hopefully HP Tuners can get that one working too so I can compare
 

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Discussion Starter #37
Just like in my tuning thread there is Operating system versions for the transmission.

My 2014 Limited= 68241136AE = Does not read in HP Tuners
Friends 2014 Trailhawk (His PCM is tuned) = 68241136AA = Does not read in HP Tuners
Friends 2016 Trailhawk = 68312133AD = Readable in HP Tuners
My 2016 Trailhawk = 68312133AC = Readable in HP Tuners
Friends 2017 Trailhawk = 68325006AG = Not Readable in HP Tuners
 

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Since there is something like 89 different shift patterns its not cut and dried thats for sure

Maybe this is a value that needs to be changed for you




Also to note, i'm getting an error message reading my 2014 cherokee, it has a different operating system so hopefully HP Tuners can get that one working too so I can compare

Wow thanks. I'll keep my dreams alive.
 

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Discussion Starter #39
I have been working with HP Tuners a lot over the past week as they finally got the support working for the transmission to be read. The issue was that I was unable to actually Write any changes.

I am no means going to try and program this myself and will leave it up to a professional tuner to do so. With all the shift patterns its really hard to figure out which pattern corresponds to what particular driving style i'm doing at a particular point in time.

I"m most interested in changing shift parameter for Sport mode and sport mode only, that way everything else can be stock.

Issues with Sport mode as its programmed from stock, it does not downshift in to first gear from a roll. Auto mode does not have this issue.

I did manage to raise the RPM limit up slightly to 6800rpm, which is about where I want it to shift, maybe 1000rpm higher. Stock is
~6250rpm.



Stock





I looked forward to having this tuned properly and finally being "done" my cherokee as this is the last thing I need to do.
 

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Thanks for the update! So I timed the 0-100 Kph on the video (unscientifically) and got 6.25 seconds.......awesome!
 
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