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Discussion Starter #1
I've only got 400 miles on my TH but I've noticed that when I have it in sport, track or custom mode and stomp on the gas the TH will slow at the shift points (around the 7K rpm mark), almost like it hesitates to shift. Anyone else notice this? I'm sure a tune would soften this, just wanted to see if this was normal.
 

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Not normal. Mine, others, and the SRT I owned previously shifted extremely quickly and firmly right at redline when going WOT. Redline/WOT shift point is 6000rpm, not 7000.

And when it shifts it isn't slowing down... just keeps pulling hard, as it should. I have 450 miles on mine. I've made several 0-60 WOT pulls to this point, and other 2nd and 3rd gear rolling pulls to WOT. Even in Auto mode is shifts well... but noticeably quicker/firmer in Sport and Track.
 

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Yeah I wouldn't say its normal for it to be shifting slower when its in sport mode. Though I don't know how you would go about identifying issues if the car isn't throwing any codes.
 

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Discussion Starter #4
Appreciate the replies. I'll play around with it some more and so if anything changes through the "break in" period.
 

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Yes during break in period there is quite a bit of torque management during upshifts.

I have noticed reduced power and lazy shifts. Still only 280 miles on the clock.
 

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Yes during break in period there is quite a bit of torque management during upshifts.

I have noticed reduced power and lazy shifts. Still only 280 miles on the clock.
I haven’t noticed any change at all. I don’t think there’s anything that’s being governed at all for a so called ‘break in period’. I’ve asked a couple of dealers that have confirmed the same.
 

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What ended up fixing this? Got 900 miles on my TH. At high rpm shifts it almost feels like fuel is cutting out for a second causing it to very biefly throw you forward between shifts. It's more noticible in sport and track the higher the rpms. Being the worst WOT in track mode.
 

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I think that's just the engine's torque management system (or what ever they call it) working to reduce shift shock.

Have you run any 0-60s with the perf pages?
If so, what numbers are you getting?
 
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Reactions: Mike Comp T/A #57

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The only time I launched it using 0-60 timer I got 3.3 and it shifted perfect. Smooth quick shifts. But it was in auto. I'm weary about taking it to dealer and telling them to run the piss out of it in track mode. Then again I guess it's no different than me driving. The delayed shifting just takes away from the whole experience. Literally gives you a little bit of whiplash. Throwing your head forward then back to full power. I talked to guys at livernois and they said they heard a few complaints and their trans tuning helps resolve it. I don't want to void my warranty just to fix a flaw. I do see a TSB on trans programming with Fca so maybe I'll just take it to dealer Although nothing related to bad shifting in the tsb.
 

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OK that sounds like possibly something not right.

My TH doesn't "Literally gives you a little bit of whiplash. Throwing your head forward then back to full power."

Check it out and let us know what you find.
 

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Auto drive mode. Not using paddle shifters. But honestly, it feels about the same as if I was using paddle shifters and hitting Rev limiter. It may be a little exaduration when I say whiplash but it deffinetly stops pulling for a brief moment between shifts at WOT in track or sport. Probably less than half a second but with that kind of power it's enough energy to make your head bounce forward and back again. I'll respond after I take it to dealer.
 

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Timing is pulled at each shift. That's why there is the Fart sound at each shift under full acceleration.
I love that sound.
 

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Timing is pulled at each shift. That's why there is the Fart sound at each shift under full acceleration.
I love that sound.
Mike that's interesting. I've noticed in my TH (@610 miles) that it seems to "fart" more at fully throttle in track and sport modes than auto mode. Do you have any additional info regarding the pulling of timing?
 

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Mike that's interesting. I've noticed in my TH (@610 miles) that it seems to "fart" more at fully throttle in track and sport modes than auto mode. Do you have any additional info regarding the pulling of timing?
Torque management
 

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Mike that's interesting. I've noticed in my TH (@610 miles) that it seems to "fart" more at fully throttle in track and sport modes than auto mode. Do you have any additional info regarding the pulling of timing?


Track sport and auto have different trans gear shift speeds programmed. Track is quickest and most aggressive.


The more aggressive the shift, the more pronounced the sound becomes.




Sent from my iPhone using Tapatalk
 

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When I read "The more aggressive the shift, the more pronounced the sound becomes." I thought it said "sh*t".
That made made laugh out loud!
 

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Took it to dealer. Had them perform a tcm flash. It was a TSB reguarding trans and transfer case. I can say it made a difference! Not just if how it shifts but it seems to find the optimal gear easier. I reccomend anyone takes theirs in if you think it has clunky shifting. Made a difference!
 

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Took it to dealer. Had them perform a tcm flash. It was a TSB reguarding trans and transfer case. I can say it made a difference! Not just if how it shifts but it seems to find the optimal gear easier. I reccomend anyone takes theirs in if you think it has clunky shifting. Made a difference!
Glad it worked out!
 

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I realize this is an older post but thought I would comment based on our experience with this platform. As Black Track stated previously this is most likely torque management (TM) that you are feeling at the shifts. The factory "Torque reduction" between shifts is very aggressive and it will feel like the vehicle is slowing down at the shift in many cases. This can be resolved with TCM tuning and customers often ask us to reduce or remove the TM. I have never seen it as bad as to cause a whiplash" affect but it is very noticeable. I would describe it as a "burble" between some shifts which is the sound of the PCM removing a bunch of timing between the shifts to soften the impact on the trans and drive train. If anyone is interested I have attached a copy of a torque reduction table. This is from a Trackhawk I am tuning for a customer in Dubai. This is the stock table to give you an idea of how much timing can be pulled at the shifts. The area circled in red is where most daily driving occurs. In this customers case we are making major changes to his TCM including 7000rpm WOT shifts, but even with those changes I am not going to modify this torque reduction table very much.
 

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