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Transmission Control Valve Recall

Whip

By Whip
in 6.6L Duramax Diesel (L5P)

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Whip Enthusiast

Whip

Posted
Posted

I posted this reply to a diiferent thread, but am reposting it here hoping that more might see it. 

 

I just had my truck in for the recall addressing the rear wheel lock up issue yesterday.  I'm very disappointed in the "solution" that GM came up with to address it. All it amounts to is a software update that will monitor wear on the valve body.  When it detects that you are within 10,000 miles of a potential failure it will immediately throw the truck into Limp mode and limit you to a max of 5th gear. They have no intention of replacing any parts or doing a real fix until you actually have that happen. 

 

I'm headed to AZ next month - 1,500 miles from home.  5th gear item going to get me and an 8,000# trailer back home. Dealer said that these valve bodies can take months to get on back order.  So am I supposed to just roll the dice and hope it doesn't happen? I can't  sit 1,500 miles from home waiting on a part. I have zero confidence in this truck to take it on any long trips.  And GM apparently has no plan to change anything in the future until i might actually be limited to 5th gear, so all future trips will come with the same fear.

 

All this recall does is cover GM from liability.  It does not fix the problem. They are going to let the owners sit wherever they happen to be at the time a potential failure is detected.  They absolutely need to reengineer the part that can cause the failure and replace it.  Or at a bare minimum at least give us a warning 5,000 miles before throwing it into Limp mode and effectively disabling the truck wherever it happens to be. 

davidm767 Enthusiast

davidm767

Posted
Posted (edited)

Honestly at this point I'm looking more and more into the NextGenDiesel Project Carbon 10L1000 DIY Valve body upgrade. I might just consider it as a $800 insurance policy. My wife's 3.0L Valve body took a dump last year and when they replaced it, the replacement failed immediately at the dealership. They ended up replacing the whole transmission with less than 5,000 miles on the "truck". I've been very lucky so far with smooth shifting and no problems after putting 4k miles on my '24 2500HD towing my 5th last year, but as the truck gets a little older and I start putting more miles on it I might just spring to do the project as a CYA.

Edited by davidm767
Whip Enthusiast

Whip

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  • Author
Posted
On 12/27/2024 at 11:55 AM, davidm767 said:

Honestly at this point I'm looking more and more into the NextGenDiesel Project Carbon 10L1000 DIY Valve body upgrade. I might just consider it as a $800 insurance policy. My wife's 3.0L Valve body took a dump last year and when they replaced it, the replacement failed immediately at the dealership. They ended up replacing the whole transmission with less than 5,000 miles on it the "truck". I've been very lucky so far with smooth shifting and no problems after putting 4k miles on my '24 2500HD towing my 5th last year, but as the truck gets a little older and I start putting more miles on it I might just spring to do the project as a CYA.

Are you thinking about installing yourself?  It's probably more than I woukd want to tackle, but my wrenching skills are limited.  I also wonder how it would cause any conflict with GMs software "fix", and what would happen if it ever threw a code for the transmission control valve. I'm sure you'd be on your own at that point. 

AndrewF Enthusiast

AndrewF

Posted
Posted (edited)

I called next gen about this a few months ago. Supposedly install doesn’t require any sort of tuning, and from reading the instructions and watching a few videos doesn’t seem too complicated for a decent or better diy mechanic to do. The only problem according to them is the upgrade is not factory “approved” and can void warranty. So for me it’s a waiting game, maybe GM will come up with an actually solution or recall to fix on their own, but either if my warranty runs out or if I have an issue and there still is a multi month lead time to get a new valve body I’ll just install it.

Edited by AndrewF
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Whip Enthusiast

Whip

Posted
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Posted

I hadn't even thought about how it might affect the warrenty on the rest of the power train. I don't think I'd want to take a chance on voiding that.  

At this point I've started shopping for a different truck.  It won't be a GM.

If we start seeing many reports of trucks going into limp mode and sitting waiting for parts that don't exist, I wonder what that will do to the used GM truck market. Thinking I might not wait around to find out. 

  • Like 1
105s New Member

105s

Posted
Posted

From what I've read GM's answer to this is to install a software patch that monitors the transmission and if a possible fault is detected it limits the use of the vehicle. So, in other words, they aren't gonna really fix anything only kick the can down the road. Also from what I read they are issuing this recall in stages to prevent the dealerships from being overran with service requests. I checked my VIN number and it isn't in the recall list yet, I expect that it will be eventually. A neighbor of mine with a 2025 2500HD has already had issues with his too, fault in the transmission.

  • 3 weeks later...
Chevyfan3 Enthusiast

Chevyfan3

Posted
Posted
12 hours ago, No F-bdy Bs said:

Does this apply to the 10spd behind the 6.6 gas as well? 

For the early years that the recall includes no, those were 6l90's. 

 

24' up gassers get the same bum Allison 10spd and can experience the valvebody failure.

  • 1 year later...
Courtney Johnson New Member

Courtney Johnson

Posted
Posted

After I had the software update, the dealership told me it is just a matter of time until the truck strands me in 5th gear.  They suggested I send an email to the CEO of GM ([email protected]).  I did so, and politely explained that I do not feel safe in 5th gear (~35 mph) on the highway pulling a trailer trying to get home.  I received a call back from someone trying to explain to me that the software they are installing, they simply forgot to install at the factory! 

I suggest everyone send a similar email, maybe we can get some attention to the fact that GM is not standing behind their powertrain warranty.    

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