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Discussion Starter #1
New to the forum. Hi. Auto question.

I have a '07 6.7L with the auto. While the trans is in tow mode and while towing whenever I hit the downshift button during a hard uphill pull the downshift from 6th to 5th feels like it's slipping. The RPMs go from around 1900 to over 3000 and then settle down to around 2500. The dealer says this is normal, but it's hard for me to believe a trans slipping like this would live long. Just wondered what you all's experience is. The truck goes to the dealer tomorrow for a safety recall and to recheck the trans and I'd like some advise on how far to press this trans issue.
 

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I don’t downshift manually; I tow with the cruise control and let the truck do everything.

When my truck shifts from 6th down to 5th I feel what I believe is the torque converter unlocking as the transmission downshifts to 5th, and then locking soon afterwards. This does send the RPM higher for a few seconds and then they drop. Then when the added load is over it will shift back up to 6th.
 

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Bubbubouy is correct. The TC unlocks allows and then downshifts to 5th. Then locks up again. Annoying, but from what I have read the 5th and 6th are the weakest gearing, so I suspect it is a preventative measure from chrysler.
 

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My 08 started to do this about a month ago. About 4 days after it started, the trans let go all together and I had no forward gears. Luckily I still had reverse and I was only 2 miles from home. Now for the bad news. This problem is quite common according to my dodge dealer, it relates back to a weak sprag bearing. Unfortunately my dealership tried to rebuild mine. They replaced the sprag bearing and my overrun clutch pack. This did get the truck moving forward again for about 20 miles when it did it again. Now they are replacing the trans and the convertor. They will probably not find any debris in the trans. If you have the ability watch the trans temp. It should run between 118 and 123 degrees empty on the interstate. after mine started revving to the engine governor during downshifts out 5th or 6th to 4th gear the temps would climb to about 160 degrees empty. Also they told me that the 09's do not seem to be prone to the same problems, my fatherinlaw just bought an 09 and his trans seems to shift allot different than mine ever did (in a good way). From what they told me Chrysler is making the dealerships try and rebuild the trans first before they allow them to replace them with a new trans.
 

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Discussion Starter #5
My 08 started to do this about a month ago. About 4 days after it started, the trans let go all together and I had no forward gears. Luckily I still had reverse and I was only 2 miles from home. Now for the bad news. This problem is quite common according to my dodge dealer, it relates back to a weak sprag bearing.
Guess I've joined the club. Just got a call from the dealer and he said they need to rebuild the trans. I asked him specifically what was wrong and he said they wouldn't know for sure till it was torn apart. We got back a week ago after towing my junk on a 2000 mile round trip, so I'm glad it didn't go out away from home, however, I'm a little irked at the dealer cause the truck was in over the winter with the same complaint and at that time they couldn't find anything wrong with it. Plus, spring and fall are the seasons I use the truck the most. At least we have things going in the right direction.
 

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Don't like the sound of that. I would be curious how many readers have had problems with their 6 speed automatics...
 
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