Automatics transmissions will last a very long time if you take care of them by regular servicing i.e. changing fluid and filters.
Heat is their worst enemy, adding aftermarket coolers and / or deep sump oil pans with cooling fins along with the extra capacity of fluid will help ensure their longevity.
As to torque converters, SunCoast is the the best available, some have reported good results with Florida Torque Converters and a few have installed torque converters designated for Dodge Hemi Trucks and reported good results.
But if you up the HP and torque with a reflash as many of us have done, or tow heavy loads, you will want the bullet proof SunCoast TC.
If you remove the transmission to install a new and better torque converter,
be sure and replace the front pump assembly as it has some wear items in it that can cause problems with age. Also the new replacement front pumps are an updated design. Along with a new torque converter and front pump assembly, be sure and install a TransGo Kit, it increases line pressure and helps with holding power of the torque converter lockup clutches along with improving shifts by making them a little crisper which helps to prolong band life.
As to tunes (reflash), the Yeti tunes are top notch, I personally have been running his Stage IV Hot Tune since 2014 and it "Rocks"!
To my knowledge he does not provide any transmission (TCM) tunes at this point. But you should contact him for more information. You can find him (Yeti) on this forum by using the PM or email LINKS below:
eMail:>
memberlist.php?mode=email&u=42474PM:>
ucp.php?i=pm&mode=compose&u=42474FRONT PUMP ASSEMBLY EXPLODED VIEW
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Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
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2mic.Sec.Fuel Filter
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