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Clunk ! When Letting Off Gas

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GMC-AT Senior Enthusiast

GMC-AT

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I only drive in 4x2... almost never use the 4x4. As for the trans, it shifts and works perfect. 

  • 1 year later...
greatmizzou Enthusiast

greatmizzou

Posted
Posted

Not to Necro this thread, but I have had that noise for a while. On a long trip it started to get really loud and very obvious and shortly after my torque converter completely failed and I blew all of my transmission fluid in a white cloud behind me.  I was only 12,000 miles into a rebuilt transmission with quality parts and installed by a reputable company. I am waiting to hear what the diagnosis is this week

  • 3 weeks later...
  • 2 years later...
99BowTie New Member

99BowTie

Posted
Posted
On 10/6/2019 at 4:49 PM, greatmizzou said:

Not to Necro this thread, but I have had that noise for a while. On a long trip it started to get really loud and very obvious and shortly after my torque converter completely failed and I blew all of my transmission fluid in a white cloud behind me.  I was only 12,000 miles into a rebuilt transmission with quality parts and installed by a reputable company. I am waiting to hear what the diagnosis is this week

 

I'm very interested in what the company had to say. My thoughts jumped to torque converter when this started happening to me.

Big clunk on just the slightest deceleration, like the torque converter fans got hung up together or something.

This is a new issue for me. My slip yolk has always been tight and all my mounts are fine.

  • 5 weeks later...
greatmizzou Enthusiast

greatmizzou

Posted
Posted
On 7/2/2022 at 2:17 PM, 99BowTie said:

 

I'm very interested in what the company had to say. My thoughts jumped to torque converter when this started happening to me.

Big clunk on just the slightest deceleration, like the torque converter fans got hung up together or something.

This is a new issue for me. My slip yolk has always been tight and all my mounts are fine.


 

The transmission shop said the torque converter exploded.  No real cause known because I barely pulled with it as it was and Im like grandpa level driving speed/acceleration.

 

they replaced it at a huge discount for me because it happened JUST out of warranty lol. 
 

Ive had some theories and one of them is poor engine grounding.  I read it is possible that electricity can arc in strange ways and cause pitting, which may cause early wheel bearing failures and maybe transmission failure too?.  I cant imagine that happening so fast on a rebuilt transmission so I would guess installer tech error or faulty part is much more likely. 

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