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Old 05-26-2014, 05:36 PM   #1
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Default Actual trans failure rate put into perspective

For those in a hurry, here is the bottom line (analysis below):

Worst Case Scenario: Transmission Failure Rate of 0.48% or a total of around 370 transmissions (more than likely, much much less than that)


Analysis

In an informative Autonews article (referenced below), among other things, they examine the dealer part records and estimate the weekly orders for new transmissions on the Cherokee:

"According to dealership parts records, Chrysler stores in the United States are ordering an average of about a dozen replacement Cherokee transmissions collectively per week under warranty."

It is not clear if the 12 replacements weekly is only happening now but, for the purposes of this analysis, I will assume it was an average number since the start of production (very unlikely, I know, but also a conservative estimate). It may also be that they are talking about replacement parts and not entire transmissions but again conservatively I assumed each one of those is a new transmission.

Also according to GoodcarBadCar, there have been approximately 76,900 Cherokees sold in the US, since October 2013.

Extrapolating all this data, from November (there were only a few hundred Cherokees delivered in October), at the rate of 12 weekly, this equates to about 336 new transmissions. Adding another 10% for Canada, this rounds off to a total of 370 new transmissions!!!! As a percentage of total sales, this would indicate a transmission failure rate of 0.48%. Note that the number is very likely lower (perhaps 1/3 or even 1/4 of this), as I was pretty conservative in the estimates, but this would probably be the worst case scenario.

Here is what the FCA CEO had to say in the same article:

"There are always teething issues with every transmission I've ever built, and I mean that literally," Marchionne told reporters at an event in Michigan. "We keep tuning the transmission more and more as we get more familiar with it.

"I'm never satisfied, but I think I'm OK with its application in the current car," Marchionne said. "It will get better six months from now, trust me."

http://www.autonews.com/article/2014...-a-reset-again
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Old 06-30-2014, 03:33 PM   #2
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Quote:
Originally Posted by cruiser54 View Post
For those in a hurry, here is the bottom line (analysis below):

Worst Case Scenario: Transmission Failure Rate of 0.48% or a total of around 370 transmissions (more than likely, much much less than that)


Analysis

In an informative Autonews article (referenced below), among other things, they examine the dealer part records and estimate the weekly orders for new transmissions on the Cherokee:

"According to dealership parts records, Chrysler stores in the United States are ordering an average of about a dozen replacement Cherokee transmissions collectively per week under warranty."

It is not clear if the 12 replacements weekly is only happening now but, for the purposes of this analysis, I will assume it was an average number since the start of production (very unlikely, I know, but also a conservative estimate). It may also be that they are talking about replacement parts and not entire transmissions but again conservatively I assumed each one of those is a new transmission.

Also according to GoodcarBadCar, there have been approximately 76,900 Cherokees sold in the US, since October 2013.

Extrapolating all this data, from November (there were only a few hundred Cherokees delivered in October), at the rate of 12 weekly, this equates to about 336 new transmissions. Adding another 10% for Canada, this rounds off to a total of 370 new transmissions!!!! As a percentage of total sales, this would indicate a transmission failure rate of 0.48%. Note that the number is very likely lower (perhaps 1/3 or even 1/4 of this), as I was pretty conservative in the estimates, but this would probably be the worst case scenario.

Here is what the FCA CEO had to say in the same article:

"There are always teething issues with every transmission I've ever built, and I mean that literally," Marchionne told reporters at an event in Michigan. "We keep tuning the transmission more and more as we get more familiar with it.

"I'm never satisfied, but I think I'm OK with its application in the current car," Marchionne said. "It will get better six months from now, trust me."

http://www.autonews.com/article/2014...-a-reset-again
i was talking with my old pappy who is a a retired 5 star Chrysler mech. about the transmission issues, he went another route, after taking in all info on what the transmission is doing, his FINAL THOUGHT", the transmission fluid may not be thick enough to give proper pressure through the Vein? and this would trick the active driveII in theory, into thinking that it wouldnt be appropriate to shift on into 8-9th gears.. due to lack of pressure, he also stated that the transmissions DOG CLUTCHES dont wear as fast as a standard clutch do to lack of friction and because they lock in , so the more miles on one would tale the tail, it kind of makes sense. and the fluid is one of a kind.. and expensive.. but to him its still beta because its so new.. he also stated that IF the software updates to the shift points do not correct the behavior that would be his move, he also said the thickness may need to be equal to what 5 weight oil would be.. figured id throw that out on here, to see what others may think..
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Old 07-01-2014, 06:07 PM   #3
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The latest flash and learning procedure is getting excellent reviews.

Perhaps the software has to be better at adjusting the movements of the dog clutches related to fluids used?

As for 8th and 9th, that's a decision the PCM makes.
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Old 07-01-2014, 07:52 PM   #4
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he also stated that the transmissions DOG CLUTCHES dont wear as fast as a standard clutch do to lack of friction and because they lock in
That is true if and only if they are properly synchronized, otherwise the "teeth" will grind and wear quickly. On the KL transmission mechanical synchronizers were deemed too bulky so synchronization is done solely by the computer which is why is is so critical that the software is right and so many updates have been released.
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Old 07-02-2014, 01:10 AM   #5
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That is true if and only if they are properly synchronized, otherwise the "teeth" will grind and wear quickly. On the KL transmission mechanical synchronizers were deemed too bulky so synchronization is done solely by the computer which is why is is so critical that the software is right and so many updates have been released.
just got mine updated today, big difference, much smoother all around in auto mode, but the manual still is a mystery to me.. is it seriously manual or is it micro managed by the system also?

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Old 07-02-2014, 10:20 AM   #6
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The latest flash and learning procedure is getting excellent reviews.

Perhaps the software has to be better at adjusting the movements of the dog clutches related to fluids used?

As for 8th and 9th, that's a decision the PCM makes.
that makes sense,
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Old 07-02-2014, 05:03 PM   #7
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just got mine updated today, big difference, much smoother all around in auto mode, but the manual still is a mystery to me.. is it seriously manual or is it micro managed by the system also?
Any auto with a "manual" mode is "micro-managed" by the computer. You send the computer a request to go to a certain gear, if certain parameters (speed, throttle position, rpm, etc.) are within limits for that gear it will go to that gear, if not it will go to the nearist gear where those parameters are met. If it can't maintain speed in a certain gear it won't go there, if a gear is insufficent for throttle position (you select a too-high gear and try to accelerate) it won't go there or will automatically down-shift, if going to a certain gear would go over the rev-limiter it won't go there, etc. So for example you can throw it into 1st at 100 mph and blow the engine, or start from a dead stop in 9th, if you select a high-gear and step on the gas it will down-shift, etc.
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Old 07-02-2014, 05:08 PM   #8
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Any auto with a "manual" mode is "micro-managed" by the computer. You send the computer a request to go to a certain gear, if certain parameters (speed, throttle position, rpm, etc.) are within limits for that gear it will go to that gear, if not it will go to the nearist gear where those parameters are met. If it can't maintain speed in a certain gear it won't go there, if a gear is insufficent for throttle position (you select a too-high gear and try to accelerate) it won't go there or will automatically down-shift, if going to a certain gear would go over the rev-limiter it won't go there, etc. So for example you can throw it into 1st at 100 mph and blow the engine, or start from a dead stop in 9th, if you select a high-gear and step on the gas it will down-shift, etc.
The whole frickin country is micro-managed!!!
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Old 07-03-2014, 01:48 AM   #9
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The whole frickin country is micro-managed!!!

well thats a
on a good note, my TrailHawk 4 Banger made a Firebird v6 or v8 i dunno? I made it look bad on a crooked back road and ticked off the driver. he came up on my 6 pretty quick so i tested the shifting a little under harder acceleration.. and clicked sports..
in my honest opinion manual is almost worthless on the road, 3rd & 4th are ok if ya like slapping the shifter .. on back roads & mountains, sports mode works well enough on its own .. impressive actually.
Manual is best used for select speed and down hill assist.. in my opinion..
I am very pleased at the moment with what the updates did for the shifting issues.. no more lag when taking off on a hill from dead stop. and the feeling like it was in between sports and auto is gone as well..
in a few weeks or less.. i hope to test out at this place.. www.windrockpark.com

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Old 07-03-2014, 09:32 AM   #10
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I've heard the sport mode is pretty awesome.
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Old 07-22-2014, 09:46 PM   #11
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speaking for my KL only.. the software upgrade seemed to work at first, now its unpredictable.
one day , it wont pull out of its own tracks and you have to floor it, then like today, you barely mash the gas and it wants to launch like a rocket ship.. this is in auto mode.. its having difficulties on the highway shifting down to a suitable gear to pull its own weight.. especially on cruise control..

using cruise control is horrible after the upgrade.. it will not maintain speed.. it goes way over.. and or way under on soft rolling hills.

i must add after the trans flash, the shifting is smooth. no problem their.. im getting tired of the unpredictable nature of the computer.
i have a Sahara and a RUbicon picked out already.. im just about ready to let the KL go..
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Old 07-30-2014, 01:27 PM   #12
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I don't know about the 0.48% failure rate but my 3 month old 1800 mile Trailhawk had to be towed yesterday to the dealer for transmission problems and I see an awful lot of posts and complaints about transmission problems.


Follow up received a call from dealer I had In Drive module from State Farm Insurance plugged into the EMC plug and that was causing fault codes, they cleared the codes and reprogramed, I hope this takes care of the problem. I will follow up with State Farm on the issue.

Last edited by Nicholl12; 07-30-2014 at 06:04 PM. Reason: New information
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Old 07-30-2014, 05:39 PM   #13
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I don't know about the 0.48% failure rate but my 3 month old 1800 mile Trailhawk had to be towed yesterday to the dealer for transmission problems and I see an awful lot of posts and complaints about transmission problems.
It is honestly too early to truly have a good perspective on failue rates. Givin the complexity of the 9-speed auto there are planty of things that can go wrong and lots of new ideas introduced on this transmission, plus it is highly dependent on software that is known to be flawed and they are working the bugs out of as they go.

Among other things flawed software could cause accelerated wear that might not show for 10s of thousands of miles (but well before the "normal" life of an automatic transmission) and under-built components will often act in a similar manner (not necessarily failing right away but not lasting as long as they "should").

It will be interesting to see how this all pans out but it certainly has the potential to be Ultra-Drive part II (for those of you not familiar with the early Chrysler "Ultra-Drive" transmissions, very few made it past 50k mi or so, they were later improved to be "ok" but were never exceptionally reliable).

I certainly wouldn't buy a vehicle with that transmission for at least 4-5 years to get a good idea of long term reliability (by that time there will probably be a lot of fleet and "heavily-driven" vehicles with over 100k mi on them to get a good idea of how they hold up) and make sure all the "bugs" are worked out of the software and design.

Last edited by dmill89; 07-31-2014 at 05:09 PM.
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Old 08-17-2014, 07:12 PM   #14
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Default Transmission failure

My trailhawk is four months old and has 6500 miles on it. Today while attempting to shift from park to drive the transmission would not move at all and the dash check engine, D Drive lights among others flashed and the on board computer stated "service transmission restart in park with zero speed." I managed to shift to drive and the transmission made a terrible clunking sound like the tranny was going to drop out onto the pavement and it would not shift out of whatever gear it was stuck in. Luckily, I was only about 3 miles from my house so I limped the vehicle home doing 20 mph the entire way.
When I got home I tried to shift it into park, the transmission is now stuck in neutral. Because of this I can't turn the key to the full off position and therefore had to disconnect the battery because all of the dash lights had stayed on. Unfortunately, it is Sunday night but I will keep those interested posted when I call the dealership tomorrow.

Last edited by Decemberist; 08-17-2014 at 10:51 PM.
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Old 08-17-2014, 09:57 PM   #15
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My trailhawk is four months old and has 6500 miles on it. Today while attempting to shift from park to drive the transmission would not move at all and the dash check engine, D Drive lights among others flashed and the on board computer stated "service transmission restart in park with zero speed." I managed to shift to drive and the transmission made a terrible clunking sound like the tranny was going to drop out onto the pavement and it would not shift out of whatever gear it was stuck in. Luckily, I was only about 3 miles to my house so I limped the vehicle home doing 20 mph the entire way.
When I got home I tried to shift it into park, the transmission is now stuck in neutral. Because of this I can't turn the key to the full off position and therefore had to disconnect the battery because all of the dash lights had stayed on. Unfortunately, it is Sunday night but I will keep those interested posted when I call the dealership tomorrow.
this may sound silly, but mine did the same thing, after it blew oil out all over the engine.. but in its craziness it lost the transmission? but nothing broke.. it does not make sense to me at all.. lol..
please do keep us posted.. and good luck.. call chrysler also.. it seems the computer is doing silly things at random.. how to pin point it i would say a flight simulator would be needed to catch it in real time when it happens..
i was too mad to find out what codes were thrown out their.. if you can see if the tech will tell ya.. and let us know..
good luck..
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