The LS/LT (M13) transmission is "D" (document attached). GM's info states 295lb-ft the same as Tremec.
The SS (MM6) transmission is "B" with the "C" first gear. I just checked GM's info and it does say 500lb-ft*.
The ZL1 (MJK) transmission is "E" with a 0.54 6th gear. GM's info states a 650lb-ft rating, like the Tremec document.
The ZL1 1LE (MH3) transmission is "E". GM's info states a 650lb-ft rating, like the Tremec document
*If you check out the Tremec "Magnum" and "Magnum XL" specs, they are listed at 700lb-ft. I know that, for the most part (99.99%), the TR6060 (the MM6, MJK and MH3 in this case) are similar to the Magnum versions. The SS (MM6) has the same ratios as one of the Magnum XL versions; maybe there is a difference in the gear construction?
http://www.tremec.com/menu/magnum/
http://www.tremec.com/menu/magnum-xl/
https://tremec-blog.com/the-differen...-6060-6-speed/