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Discussion Starter #1
my auto tranny has developed a new issue. when slowing down, the tranny "bucks" at 29-30 mph, when it is downshifting. its a single thump.

so far, it only does under this precise scenario. it doesn't seem to do it under heavier braking though (through this speed range).

thoughts?
 
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I have the exact same problem. I currently have 8000 miles on the odo. I will be taking the Rubi in next week.
 

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Discussion Starter #3
i'm knocking on 8k too. post back when you find out what it may be. i made an appointment for the 8th to get it looked at.

i am guessing the answer will be "sorry mr. holmes, our technician couldn't duplicate the problem."
 

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Auto Tranny Bucking at 30mph

Guess what guys? Been there - Done that - Got the t-shirt!
My auto was downshifting with a hard thump every time consistently at 30mph. However it did not do it with the overdrive off (OD light on). Pisses ya off don't it? Anyway I took it to dealer and told him to reflash the PCM Module (powertrain control module) The transmission control module in particular. Guess what - problem went away and my accelleration even got better! Prior to this always thought mine was a little sluggish on the accell. for a fuel inj. six. Try it, you'll like the results! :)
 

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You're not alone, I too have noticed the "thump" when decelerating. Doesn't bother me though. But do let me know what you find out from the dealer.
 

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Recurring Auto. Trans Problem

Well heck - it seems the problem with the hard downship at 30mph is back. Reflashing the Trans control module helped since June 27, but it has returned. Dealer just informed me they contacted DC hotline and they are aware of this problem. Seems the front trans pump is losing its prime resulting in the "thump" while the auto trans downshifts at 30mph. Seems reflashing the control module justs resets all the values which is a temp. fix. DC is fixing by replacing the pump and according to them takes care of the problem. Of course pump is on order and should be in by end of this week. Then they have to take out trans and replace pump. We shall see says the blind man. I will post later and let you know how it turns out. :?
 

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Discussion Starter #7
replied to the other thread about this. went away for now. will wait for round two.

mine would stop briefly if i kicked OD off, but then return.
 

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Auto Trans problem Update

Dealer replaced front tranny pump which DC star hotline said would fix the problem of the hard downshift at 30mph. Seems to run well, but we shall see what happens the next two months. Keepinf fingers crossed guys!
 

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Discussion Starter #10
ugg, its started again. of course i am sure it will not do it when i take it in for service - never does. i hate this f'n transmission.

it was also slipping on inclines today (not even very severe ones). fluid level is fine.

:(
 

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My Auto just recently started acting up- build date of my Rubi is Feb 03 and it now has 4700 miles.

On Sunday, three times on trail in a very mild climb, I was crawling along and when first touching a small rock or ledge, the auto would instantly unload and reload- it was as if I hit a foot tall ledge and was stopped instantly. :shock: Very irritating. :mad: On the other hand, I was on far steeper more strenuous obstacles and it never gave a hint of trouble.

Today, hopped in to drive to work, fired it up, and threw it in drive. Rolled down the driveway, and suddenly no locomotion. :x Tried reverse, drive, 2nd, 1st, Park, drive, reverse- nothing. After about 15 seconds of messing around, the tranny finally obliged and worked normally again. :2gunfire:
 

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Discussion Starter #13
Calypso said:
On Sunday, three times on trail in a very mild climb, I was crawling along and when first touching a small rock or ledge, the auto would instantly unload and reload- it was as if I hit a foot tall ledge and was stopped instantly.
this is one of my three distinct tranny problems. i wasnt quick to call this one a tranny problem because i felt like it if was the tranny slipping, the enging would rev out of control until i took my foot off of the gas. and it doesnt really do that too much.

what sucks is that i have tons of witnesses to my tranny acting crazy, but it will never do ANY of them for the service department.
 

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the very same thing happend to me a while back..
you could hear my engine race on the vid. climbing a small rock.
grrrrrrrrrr
only happend once... can not duplicate.
:cry:
 

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Calypso said:
My Auto just recently started acting up- build date of my Rubi is Feb 03 and it now has 4700 miles....

Today, hopped in to drive to work, fired it up, and threw it in drive. Rolled down the driveway, and suddenly no locomotion. :x Tried reverse, drive, 2nd, 1st, Park, drive, reverse- nothing. After about 15 seconds of messing around, the tranny finally obliged and worked normally again. :2gunfire:
One of the guys at work here has a Liberty with the 42RLE auto. His KJ exhibited similar problems. It is now at the dealer getting a new front pump and torque converter.

Knock on wood, my auto has not given me any problems so far.

Jerry
 

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Mike Holmes said:
my auto tranny has developed a new issue. when slowing down, the tranny "bucks" at 29-30 mph, when it is downshifting. its a single thump.

so far, it only does under this precise scenario. it doesn't seem to do it under heavier braking though (through this speed range).

thoughts?
To bring this back to the "Thump" when downshifting, while I was 4 wheeling this weekend I really felt the "Thump" when in low range whenever it was downshifting, it actually felt like the transmission is doing it to prevent the vehicle from free-rolling down hill, sort of making sure it was compression braking. I think I like it, and can live with it on the road.

Just my observation, but I don’t think there’s anything wrong.
 
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I developed the buck at about 8000 on the odo. I had the PCM reflashed which took care of the problem briefly. Now the "thump" is back again at 10,000 on the odo. I guess DC needs to give everyone the computer program to reflash the PCM every few thousand miles. :mad:
 

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Re: Auto Trans problem Update

whatroc?! said:
Dealer replaced front tranny pump which DC star hotline said would fix the problem of the hard downshift at 30mph. Seems to run well, but we shall see what happens the next two months. Keepinf fingers crossed guys!
As of 7/31/03 Still doing okay - just had front drive shaft replaced, will pickup this afternoon. :2gunfire: If it still has the problem - its gonna die!!!
 

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Has there been any updates on any of these problems?

I have an Aug 02 build with the auto. I have not had it any real extreme conditions to have a problem I guess. Since it had the older style pan on it I thought I should probably do the update. and at the same time I was doing the Medic oilpan/tranny skid. seemed like a good idea. :?

We did the updated pan and filter, used DC fluids checked it all the right way blablabla. On the test drive I immediately had the hard down shift at about 30 braking with the OD on. It doesn't do it with it off.

With the old pan I had NO issues to date. None, nada, shifting was seamless up and down. I thought putting the newer pan would be a good idea since I am going to be able to get away to Gray Rocks, Tellico and Monteagle this year and we do have some pretty verticle spots at all those spots.

I think I shot myself in the foot....... I mean it's not an expensive update.
I have a good liason at the dealer, they know my Jeep, they like my Jeep but I haven't had to push anything there and I don't look forward to taking it in for a new pump with a RE longarm skid on it. :rotflmao:

I did save the old pan :wink:
Any input appreciated.......... thanks
 

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Kindofarubi said:
Has there been any updates on any of these problems?

I have an Aug 02 build with the auto. I have not had it any real extreme conditions to have a problem I guess. Since it had the older style pan on it I thought I should probably do the update. and at the same time I was doing the Medic oilpan/tranny skid. seemed like a good idea. :?

We did the updated pan and filter, used DC fluids checked it all the right way blablabla. On the test drive I immediately had the hard down shift at about 30 braking with the OD on. It doesn't do it with it off.

With the old pan I had NO issues to date. None, nada, shifting was seamless up and down. I thought putting the newer pan would be a good idea since I am going to be able to get away to Gray Rocks, Tellico and Monteagle this year and we do have some pretty verticle spots at all those spots.

I think I shot myself in the foot....... I mean it's not an expensive update.
I have a good liason at the dealer, they know my Jeep, they like my Jeep but I haven't had to push anything there and I don't look forward to taking it in for a new pump with a RE longarm skid on it. :rotflmao:

I did save the old pan :wink:
Any input appreciated.......... thanks
You were left hangin' here eh? Are you still having the problem?

When you did the pan, did you also get the longer snorkle for the pick up? I thought I read that you needed both.

Nick
 
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