trans shudder choices

A shout out to any trans specialists!

I now have 310K on my A750F trans and a shudder is back every once in a while after some "Shudder fix" 50K ago.

I did partial fluid changes at 100K intervals BTW.

should I .....

A. add another tube of Shudder Fix?
B. rebuild valve body with a Zip Kit from Sonnax https://www.sonnax.com/parts/3477-zip-kit
C. replace torque converter
D. replace trans from low mileage scrap yard unit
bring it to a transmission shop, scary...

 

Had to get a Toyota genuine reman from dealership
Be aware, always confirm good clean pin fit on all electrical connections to trans
Replacement pins are available
Scan tool will confirm

 

How much did that run you?

 

$3140 + 6 hours labor
Some exhaust work too

 

The biggest headache was techs were scratching heads not seeing why codes popped up. Loose or corroded connector pins.
My local mechanic fixed. Dealer wanted 4600 to replace harness
The pins are a Toyota part, odd

 

sounds like the best option , never again will I get screwed by "Transmission Shops", fail rate has been 100% over my lifetime (at 70 YO)
Only way is a done unit on a crate with a WARRANTY or out of a wreck
Seems this ham handed mashing of connector pins is very common, and the "mechanics" have trouble diagnosing and fixing their goofs, ( happened to me recently on an F150 dash removal)
it is scary enough having avg joes with no talent or skills working as mechanics to install it, imagine having them rebuild it LOL