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Class Action suit for transmission control module on 2008-2015 with 6.6L Duramax and Allison 1000 transmission

413 Views 1 Reply 2 Participants Last post by  heymccall
This was posted on the Duramaxforum.com, so thought I would post it here, as well, in case anyone is interested. If you want to get in on it, please contact him, not me.

General Motors produced several years of trucks with a faulty transmission control module.

From 2008 thru 2015, Chevrolet and GMC 2500 & 3500 trucks with the 6.6 L Duramax engine and Allison 1000 transmission all used the same TCM; part number 24256861. This part has experienced a very high failure rate. During the summer of 2022, the meager stock of replacement parts was exhausted. GM has told several owners that the part will be available soon, but the date keeps getting pushed out: Oct 2022, then Dec 2022, then March 2023, then April, and so on.

August of 2022, I personally had to leave my 2009 GMC 3500 HD at a GMC dealership in Layton, Utah in the middle of a 6-month RV trip. After searching for the TCM for a month, I gave up and purchased a 2021 Chevrolet 3500 HD so that we could continue our trip.

An estimated 5000 vehicles are currently unusable due to the failure of this part and no new parts available. There are multiple advertisements from a variety of sources that offer the part--often at outrageous prices--but these ads often turn out to be false and some are even scams. I have responded to several ads but the result is one of two: first, the company finally admits to not having the part but offering to ship 'something that will work'; or second, just as often, the advertisement is a scam looking to get credit card/ bank account numbers, with no intent to actually ship the product. Right now, eBay advertises the part with prices ranging from $9000 to $19000. This is a $649 retail part.

The high failure rate of the part appears to relate to the factory placement on the radiator shroud. Heat has been blamed for the failure. GM should post a bulletin to re-install new TCM's on the fender well. This tactic has already been taken in some repair shops with success. Another cause of the high failure rate is insufficient grounding of the heat sink. This is a simple fix but GM seems to ignore the issue.

It is our intent to file a class action lawsuit against General Motors to have new parts updated to resolve failure issues and manufactured in a timely manner.
If you are interested in joining this class action, email to [email protected] with the phrase "GM Class Action" as the subject.
Please comment on your experience with your 2008-2015 Chevrolet/GMC truck with the Duramax/Allison 1000 transmission.
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Looks like they are starting to hit the shelves. Haven't gotten mine yet :(
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