So THAT'S where all the extra GM muscle and Allisons went...to Russia. From the wiki article on the Dartz T-98 Kombat: "There are two basic versions of the T-98 Kombat based on General Motors components, including 8.1l engine, Allison transmission and GM Heavy Duty suspensions."
The seats in the Prombron are reportedly available upholstered in leather made from the foreskin of whale penises
...nice. Like the saying goes, "smooth as a baby whale's penis."