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BAMDmax
10-09-2013, 08:41
Hi Guys!
I'm new to the diesel world and this site. I have bought a used 2012 Chevy 6.6 Duramax with 37,000 miles on it. It has been shifting hard on the downshift side from like 6th down to 5th and maybe 5th to 4th, but that is it. I took it back to the dealer and they said somebody changed the filter and it was leaking so they put a new one on and topped off the fluid. I drove it home on the highway and it seamed to be fine. The next day it started shifting hard again so I checked the fluid myself because I didn't know if they followed the correct steps. I went directly by the book and checked it and it was 1 qt low. So I filled it up to the correct level. I drove it to work yesterday and it is hard shifting again. What in the world is going on here? I called the dealer and setup an appointment for tomorrow. They told me that it could be a normal thing. That the tranny has learned the way the previous owner drove. I told them that if it was normal I wouldn't have bought the truck. What do you guys think it could be? Could they be trying to blow smoke up my butt? If the tranny is trained to the way somebody else drove is there a way to reset it to the way I drive? Thanks for any info, It would surely be appreciated.

rapidoxidationman
10-09-2013, 18:19
If it was "learned" behavior then it wouldn't have felt better after the dealer serviced it. Also wouldn't be a quart low after a day - are you sure you checked it hot? Any codes present in the OBD?

If it's a four wheel drive, how does the fluid level in the transfer case look? I'd wonder if there isn't a leak between the transmission and the transfer case. Any sign of leaking on the outside of it all?


My experience ends with the model year 2005, so I may not know WTF I'm talking about, YMMV, and this advice is worth what you paid for it...:cool:

BAMDmax
10-10-2013, 07:29
I looked to see if anything was leaking and didn't see anything. I was the one that noticed the filter leaking the first time. I did however smell a strong ATF (like it was very hot or burning)when I got out of my truck to go to my treestand hunting last night. I guess I'll have to wait and see what they say at the dealer.

More Power
10-24-2013, 13:07
I recommend reading the following thread: http://www.thedieselpageforums.com/tdpforum/showthread.php?t=16809

Here's a quote from the above:


"The LCT1000 as set up in the GMC product will not enter the fast adapt mode through a gear selector routine. In order to enter fast adapt learn mode the tcm must be cleared and the process started using a Tech 2. There is a series of service bay shifts to be performed and then aprox. 12-14 additional shifts while driving to complete the "fast" stage of the relearn process.

Also, see: http://www.thedieselpageforums.com/tdpforum/search.php?searchid=301083