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Posted
57 minutes ago, the8rotor said:

@Agargano98 let us know how it goes getting that fixed. Really sucks man. 

Going to the dealer first thing in the morning.

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Posted (edited)
On 7/6/2023 at 9:29 PM, UWSkier said:

That's a great way to describe how mine feels when downshifting into first gear approaching a stop sign or stoplight.  It makes nice linear stops kindof a pain.  I have about 400 miles on my truck so far so I'm hoping that improves.  It's going on a 4000 mile RV towing trip pretty much the second it hits 500 miles.  Maybe that'll teach that transmission a thing or two.

FWIW My beloved truck used to hit me with a harsh downshift out of the blue while driving in parking lots. But it faded away nicely after about 5-10K mi. Can still reproduce it in specific situations, but its mostly gone. 

 

Slightly off-topic:

The truck used to also have a clunk coming intermittently from the rear leaf pack. This too has mostly faded away but not completely. I would have torqued the bolts up real good by now, except I'm gonna throw them away and install new leaf packs / air bags in two weeks.

 

And while I'm off-topic:

After about 20K mi, the computer has finally adapted well to driving style. While not towing, it now consistently holds a gear during long hill descents. It's unexpected. A big improvement. 

 

 

Edited by NaturallyAspirated
Posted

I am certainly happy to hear that the transmissions seem to settle down nicely after having some mileage put on them.

Sorry to see other members are experiencing the same drip from the transmission that I did.  I have 400 miles or so since my transmission replacement and so far I don't see any leaks. Keeping my fingers crossed.

A issue that keeps popping up is my front passenger signal has an intermittent not functioning with the fast clicking on the dash.  Repair shop got back to me today and said there is a tsb that came out a few weeks ago for this issue. Evidently it has to do with some sort of programming in the light.  They have a  new light on order and will be replacing the one I am having the intermittent issues with.

Posted
On 7/19/2023 at 7:03 PM, Agargano98 said:

Just looked under my 2024 gasser at 1000 miles.

20230719_185025.jpg

Sorry to hear you are going thru this as well.  I am here in CT as well and ONeils in Avon has been taking care of me.

Posted

Sorry to hear all this, fellas. I also experienced the harsh downshifting when coasting to a stop, but it has seemed to stop doing it after about the 1000-1500 mile mark. I'm new to HD trucks and also notice a light, high-pitched squeak or squeal in between shifts, mostly through the first few gears (maybe the road noise masks it at higher gears?). Has anyone else noticed that, or is it normal with these larger transmissions?

Posted
On 7/28/2023 at 12:56 PM, BuckWallace said:

Sorry to hear all this, fellas. I also experienced the harsh downshifting when coasting to a stop, but it has seemed to stop doing it after about the 1000-1500 mile mark. I'm new to HD trucks and also notice a light, high-pitched squeak or squeal in between shifts, mostly through the first few gears (maybe the road noise masks it at higher gears?). Has anyone else noticed that, or is it normal with these larger transmissions?

That high pitched squeal is the allison transmission just making noise. 

Posted
1 hour ago, the8rotor said:

That high pitched squeal is the allison transmission just making noise. 

Thanks, so are you saying this is a normal noise?

Posted
On 7/27/2023 at 8:15 PM, stympyctlan said:

Sorry to hear you are going thru this as well.  I am here in CT as well and ONeils in Avon has been taking care of me.

Dealer took a look today, the forward internal cover is leaking around the perimeter.  They ordered a new cover, perimeter seal, and shaft seal.  They topped off my fluid (less than a quart) and sent me on my way.  They said probably a week or two for the parts to come in.

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Posted
On 7/31/2023 at 11:39 PM, Agargano98 said:

Dealer took a look today, the forward internal cover is leaking around the perimeter.  They ordered a new cover, perimeter seal, and shaft seal.  They topped off my fluid (less than a quart) and sent me on my way.  They said probably a week or two for the parts to come in.

Good to hear they appeared to have found the issue. 

  • 4 weeks later...
Posted

Front cover seal replaced.  Ended up leaking again, and the transmission developed bangs and jerks when downshifting and coasting downhill.  Dealer verified and ordered brand new transmission.  Hopefuly will be fixed in a week or so.  

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Posted

this is awesome.  just looked under my 24 duramax and have the exact same image.   I guess they can look at this when they look at the flooded camera and flash the truck so the fog lamps light up.  Really sad we can't get better quality when they want this kind of money for these trucks.  mines just an LT, and i still feel like it was 20k overpriced.  the dash has rattled since i brought it home, and the camera took a poop with about 5k miles on it.....now the oil leak/seals whatever.......this has been an issue at the engine/transmission connection point since before 14' because my old 14 did it from about 60k on, until it was traded......but that was engine oil so i guess this is "different" lol

Posted
On 8/28/2023 at 11:58 AM, Agargano98 said:

Front cover seal replaced.  Ended up leaking again, and the transmission developed bangs and jerks when downshifting and coasting downhill.  Dealer verified and ordered brand new transmission.  Hopefuly will be fixed in a week or so.  

 

Please update us.....Did you ever get the new trans?

Posted

Sorry, haven't been here for a while.  Yes they replaced the transmission with a new unit.  Almost 1000 miles and no issues yet.  Keeping my fingers crossed.

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Posted
4 hours ago, Agargano98 said:

Sorry, haven't been here for a while.  Yes they replaced the transmission with a new unit.  Almost 1000 miles and no issues yet.  Keeping my fingers crossed.

Good to hear! Sucks you had to deal with a patchwork "fix" the first time.

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