Something Broke

[C M McCormick]

Found them from April 2019.View attachment 124772 View attachment 124773

Yep now that is strange. Was your flex plate hitting the starter?

 

[brucejohnson]

Interesting that the heavy wear/contact points on both flex plates correspond to the stamped balance holes. Craig's flex plate shows contact at each stamped mounting hole on the contact side. Both adapters appear to be worn in the same area with (heat or stress?) cracks. Must be close clearance at that point. Bad flex plates and/or castings?

 

[sag2]

I want to say the one I saw had about 15,000 miles. Engineering had the technician measure a bunch of stuff, but other than changing the flex plate and adapter they never said (admitted) what the cause was. The one out here was also towing heavy when it failed.

 

[brucejohnson]

I want to say the one I saw had about 15,000 miles. Engineering had the technician measure a bunch of stuff, but other than changing the flex plate and adapter they never said (admitted) what the cause was. The one out here was also towing heavy when it failed.

My WAG is they need a little less flex in the flex plate, or more clearance, especially with the torque these engines are producing nowadays. They look a lot heftier than the old days being solid and all, but the lock-up torque converters apply lots more "scheduled" oomph vs. the old school high stall, no lock ups, no power regulation.

 

[Ozymandias]

With a not properly seated TC, something has to give way.

 

[DonFitzwater]

I’m just thinking out loud here......if a torque converter wasn’t seated properly, wouldn’t the front pump be damaged as well?........also, what could cause a torque converter to travel forward? I know they are held captive by design but we’ve all heard of “ballooning”. Is it possible for a fluid flow abnormality to move the torque converter by hydraulic force?

 

[brucejohnson]

Don,

Here's some reading that may help to answer your questions.

http://www.zt-corp.com/blog/archives/115/

http://atpautomotive.com/flexplate-z-108#:~:text=Vehicles with automatic transmissions have a flex plate.,of the torque converter as engine RPM increases.

https://www.carbibles.com/what-is-a-flexplate/