Coolant Control Valve - Extended Warranty

[StephenPT]

I’ve seen this failure a few times on this forum and more so on the Duramax forum - just posting this here so everyone is aware that they are providing a special coverage warranty - 15 years or 150,000 miles. Most failures I’ve seen happen around 50-60K miles on the LM2.

 

[JayceeP]

I’ve seen this failure a few times on this forum and more so on the Duramax forum - just posting this here so everyone is aware that they are providing a special coverage warranty - 15 years or 150,000 miles. Most failures I’ve seen happen around 50-60K miles on the LM2.

I don’t see the 2024 Yukon there. Do I take that to mean my 2024 has a fixed production CCV installed?

 

[StephenPT]

That's the way I would read it. The new part number is 40009644 for the LM2. Since '24 still used the LM2 and isn't on the list, then I think you have the new part number.

There's also a bulletin for the LZ0, however it only shows coverage for the Silverado because it started using the LZ0 in '23. No coverage for the LZ0 in the '25 SUVs so my guess is they changed both LZO and LM2 in 2024 MY to new CCV part numbers. Just FYI, the LZ0 uses a different CCV and has one less coolant circuit.

 

[JayceeP]

That's the way I would read it. The new part number is 40009644 for the LM2. Since '24 still used the LM2 and isn't on the list, then I think you have the new part number.

There's also a bulletin for the LZ0, however it only shows coverage for the Silverado because it started using the LZ0 in '23. No coverage for the LZ0 in the '25 SUVs so my guess is they changed both LZO and LM2 in 2024 MY to new CCV part numbers. Just FYI, the LZ0 uses a different CCV and has one less coolant circuit.

Good to know- thanks!

 

[UsualSuspect]

Here is the GM communication to NHTSA. N252508341 LM2 Coolant Control Valve Replacement

 

[JayceeP]

Great info. I’ve been a bit nervous about this but sounds like it’s been addressed in the ‘24 LM2.

 

[jsh0738]

2024 Tahoe with the 3.0 Duramax here. Mine failed at 16k miles. Took 48 days to repair due to parts availability. The dealer installed a p/n 40009179 valve. Wonder if mine is under the extended warranty? It is a LM2.