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-   -   A favor to ask of anyone with the 8spd transmission (http://www.jeepgarage.org/f73/a-favor-to-ask-of-anyone-with-the-8spd-transmission-60956.html)

nj newb 06-04-2013 10:02 AM

A favor to ask of anyone with the 8spd transmission
 
place the transmission in manual mode.

in 1st gear lightly tap the gas and release around 5mph. while coasting, upshift to 2nd gear anywhere between 5-10 mph.

Does your transmission shift rough and does it make a fairly audible clunking noise, which is also felt?

Andoskyy 06-04-2013 02:15 PM

Re: A favor to ask of anyone with the 8spd transmission
 
yes

nj newb 06-04-2013 02:28 PM

Re: A favor to ask of anyone with the 8spd transmission
 
is this something you've experienced before? do you consider this normal?

This is something i've been trying to get diagnosed and trying to find if it's across all 8spd transmissions or just a few. I have read posts about how the transmission learns driving habits and adjusts, but I don't believe this to be a reason or cause or a solution. I have 2k miles and this has been the case from day 1. Others have noted it may need a software update and I agree, seems like the mapping should hold the rpms up during the shift.

I originally noticed this while in "D" and have been able to replicate it better by doing what I'm asking you guys to try out.



Quote:

Originally Posted by Andoskyy (Post 834886)
yes


studio1930 06-04-2013 02:40 PM

Re: A favor to ask of anyone with the 8spd transmission
 
I'll have to specifically test this, but I get the CLUNK all of the time when it shifts in or out of 2nd or 1st gear (usually downshift to 2nd). Hate that.

Andoskyy 06-04-2013 09:06 PM

Quote:

Originally Posted by nj newb (Post 834890)
is this something you've experienced before? do you consider this normal?

This is something i've been trying to get diagnosed and trying to find if it's across all 8spd transmissions or just a few. I have read posts about how the transmission learns driving habits and adjusts, but I don't believe this to be a reason or cause or a solution. I have 2k miles and this has been the case from day 1. Others have noted it may need a software update and I agree, seems like the mapping should hold the rpms up during the shift.

I originally noticed this while in "D" and have been able to replicate it better by doing what I'm asking you guys to try out.

I don't consider it normal, but it also doesn't bother me. I only notice it in traffic and it remind me to chill out and leave more space between me and the car in front of me.

I'm sure if it's a problem, they'll fix it. I/we have a 100k powertrain warranty, so I'm not worried.

It's simply not worth it to me to have a dealer look at it yet.

I'll let some time pass and if there is an update, I'll have it done.

LSU_FAN 06-05-2013 10:48 PM

Re: A favor to ask of anyone with the 8spd transmission
 
I tried this today no noise and with such a low first gear you should expect to feel it shift while coasting...Especially when it's not in eco.

Nuka1195 06-06-2013 07:43 AM

Re: A favor to ask of anyone with the 8spd transmission
 
Not necessarily the same issue, but maybe this would help you.

http://www.jeepgarage.org/f107/i-thi...ion-61052.html

hemi15 07-19-2013 08:41 AM

Re: A favor to ask of anyone with the 8spd transmission
 
Yes mine does exactly what you decribed.

nj newb 07-19-2013 08:51 AM

Re: A favor to ask of anyone with the 8spd transmission
 
I gather that this is the nature of the transmission, I don't believe this is how it should work, but the fact is that it does.

I was trying to determine whether the issue is mechanical or software related, I was thinking that if this only happened when in Auto, then it would more easily isolate software related issues. Maybe it needs to keep the RPM higher between shifts.

And so I thought if this is happening with manual shifts, maybe it's something mechanical. But I don't think that would be correct to assume, since the TCM is still involved in a manual shift.

At the end of the day, it's easy to see that this is not isolated to just a few trucks, but pretty much how it was built for all of them. It will likely be resolved through a software update and it would be nice if they could expedite the fix.

Quote:

Originally Posted by hemi15 (Post 861020)
Yes mine does exactly what you decribed.


bill_de 07-19-2013 08:57 AM

Re: A favor to ask of anyone with the 8spd transmission
 
Does everybody who said yes have a V6?



---

nj newb 07-19-2013 09:01 AM

Re: A favor to ask of anyone with the 8spd transmission
 
I have the V6

Quote:

Originally Posted by bill_de (Post 861028)
Does everybody who said yes have a V6?



---


hemi15 07-19-2013 09:02 AM

Re: A favor to ask of anyone with the 8spd transmission
 
I wrote this in another tread yesterday.
Quote:

This transmission roughness became more severe and annoying as I keep driving. Today I did try some different things using the shifters in manual mode.

Stopped the car.
1-2 smooth
2-1 smooth
2-1-2 quickly car jerks.
This kind of explains rough shift when tranny cant decide which gear to choose.

Started moving.
my foot on the gas accelerating 1-2: not perfect but relatively smooth
my foot off the gas pedal car is moving 1-2: very rough, and hear a clunk

I no more think that this is a software issue. It happens in manual mode too on my car. tried the manual mode to see what happens?


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