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  #25  
Old 01-22-2015, 12:52 AM
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Re: Clunk/thunk on 6-5 coasting downshift.

And for what it's worth, overall the transmission in this is a lot more herky jerky all around than the 8-speed in the 2013 5.7L Ram 1500 I have as a work vehicle, in fact one of the reasons I wanted the 8-speed in the Jeep when I bought it was how smooth it was in the Ram truck!

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  #26  
Old 01-22-2015, 01:57 AM
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Re: Clunk/thunk on 6-5 coasting downshift.

Quote:
Originally Posted by rlarsen462 View Post
And for what it's worth, overall the transmission in this is a lot more herky jerky all around than the 8-speed in the 2013 5.7L Ram 1500 I have as a work vehicle, in fact one of the reasons I wanted the 8-speed in the Jeep when I bought it was how smooth it was in the Ram truck!

I didn't have any jerky jerky behavior in my SRT, except for the 6-5 down shift. ALL other shifts were butter smooth. The 6-5 downshift just produced a clunk/thunk noise along with jerking your body forward. again, ALL OTHER shifts were butter smooth for me.

As far as the drone goes, to my knowledge there is no activation of the MDS system by default on the 2015. You have to actually press the ECO button on the center stack to engages it. When mine was new(it only has 1551mi)no drone was present when the ECO was in the default off and only a slight drone when engaged. The drone I've got now is more like a drone/vibration that your ears feel but also your butt.

There has been a steady escalation in the drone since about 1300 miles with my trip to the dealership being uncomfortable at any speed above about 40mph.

I can understand a vehicle of this nature having some exhaust drone/vibration, but mine was pretty obvious that something was wrong. It was just way to rapid of a decline.



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  #27  
Old 01-22-2015, 03:29 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

Yeah that's different from what I'm experiencing with the MDS...I for a fact I know that the MDS DOES engage (and quite a bit) with the Eco button OFF, in Auto Selec-Track, and in D shift mode.
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Old 01-22-2015, 04:17 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

District manager is coming out today to drive my SRT with my service manager. I guess I'm not out of the woods yet. Should know the outcome tonight before 5 or mid morning tomorrow.


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Old 01-22-2015, 05:05 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

New tranny and torque converter on the way. I won't know till tomorrow when they'll have it. I may be getting it back as is until the new tranny comes in if Chrysler deems it safe to drive. I'm fine with that because the minivan rental, Enterprise set me up with smells like a Tijuana prostitute.


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Old 01-30-2015, 08:27 PM
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Clunk/thunk on 6-5 coasting downshift.

I just got finished washing my SRT after picking her up last night and putting some miles on her today. I'm happy to tell you all the new transmission is a night and day difference. No more 6-5 clunk just a nice firm shift without jerking me forward. I put about 60 miles on it since I picked it up and it just seems to be improving. I think this tranny is actually learning to improve it's shifting, unlike the original. It acts like a completely different vehicle and I'm pleased with it. I'll put some more miles on it and report back with any issues.

The only thing I wasn't happy about, was after picking it up last night, I heard a tink, tink noise then looked behind me and saw something in the road. I thought it was a socket at first, but then doubled back to be sure. Turns out it was about a four inch long bolt, so I picked it up out of the roadway and burnt me fingers, confirming it was from my SRT. So I high tailed it back to the dealership to make it there before close. Turns out it was one of the bolts holding the exhaust to the exhaust manifold on the left side. Tech promptly reinstalled it and apologized and I was on my way.


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  #31  
Old 01-31-2015, 06:46 AM
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Re: Clunk/thunk on 6-5 coasting downshift.

Good to know your persistence paid off. I had a serious clunk issue with my 07 years ago, so I know the feeling of decelerating and feeling like the truck just got rear-ended. Was disappointed to hear the problem still existed to some degree on the WK2's. Good luck with the new transmission.


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  #32  
Old 01-31-2015, 11:25 AM
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Re: Clunk/thunk on 6-5 coasting downshift.

Keep updating this thread as the transmission learns, will be good to know if it stays symptom free. Keeping my fingers crossed for a smoother experience getting this fixed than you went through, using your example.
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  #33  
Old 02-01-2015, 01:54 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

Another software update

http://www.wk2jeeps.com/tsb/tsb_wk2_2100515.pdf


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  #34  
Old 02-02-2015, 07:04 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

Confirmed that update was not applicable to 2015, mine showed as all updated already when they scanned it.

Got a call back from the service manager today, they got the transmission warmed up and put it on the rack and shifted from P/N/D repeatedly, which he claimed duplicated the same noise I demonstrated to him when downshifting from 6-5. Said they listened under from front to back and the sound appeared to be coming from the rear end but they couldn't localize it.

One of his techs tried to claim that the transmission behavior was normal backlash and programmed in due to EPA regulations, which sounded like BS to me. I mean, I understand that they are maximizing programming for mileage, but if Chrysler really intended their flagship $70K+ Jeep product to clunk and jerk all the way down the gear range they need to have their head checked.

It's not over yet, the service manager will be talking to Chrysler tomorrow and hopefully getting some info on this issue. He expressed concern several times that he didn't have another one on the lot to compare to, but I was quick to warn him just because another one does it, doesn't mean it's right (if there was a batch of bad parts or something).

If we aren't moving to a resolution of some kind by the end of the week, I will get Chrysler customer service involved directly. I wish they would just call the dealer in MI that just replaced the transmission and compare notes, but they seem reluctant for some reason.


Still no jerks from 6-5, and the clunking is gone after the replacement?
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Old 02-02-2015, 08:06 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

I'm calling B.S. as well. If it's the rear end why doesn't it clunk in every gear? All cars make noise when shifting from D/P/N it's driveline slop. My new tranny is shifting much better than the old one. It has a definite positive downshift, but that loud clunk is now gone as well as the awful vibration I was getting. I was hoping that the latest TSB would get it to near perfect. I guess i'll have to wait. I can at least live with it now unless it gets bad again. I've had a few harder than expected 7-6 downshifts(very sporadic), but still nothing like my old 6-5 downshift.



It sounds like your getting the go around like I got. I think it's because they don't know why it's doing it or how to fix it, so they have to tell you something. I'm questioning the quality control on these transmissions. They all seem to have their own personalities.



Did they inspect the mounts and bushing on the rear end assembly?





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  #36  
Old 02-02-2015, 08:51 PM
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Re: Clunk/thunk on 6-5 coasting downshift.

They made it sound like they didn't see any movement/contact so it makes me suspect they didn't actually get torque on any mounts.

I will take the SM's word for it that he's going to be in touch with Chrysler tomorrow, also I am supposed to be picking up the vehicle with no work performed at this point. I will be speaking with him daily and like I said by Friday I will be contacting Chrysler myself...trying to give them the benefit of the doubt but if this is supposedly normal I'd like to hear it directly from the manufacturer...sounds like the same pathway you took.
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