That ZF 8 speed transmission is used in a LOT of vehicles in various configurations. I had one in a BMW 535i, it was flawless in the time I had it. The 6 speed auto is a 545RFE with an extra gear basically, which is an in house transmission from Chrysler. Chrysler automatic trannies haven't had the best reputations over the years. Given the choice, I'd prefer the 8 speed.
https://en.wikipedia.org/wiki/ZF_8HP_transmission
