I have been running the V6 trans behind my V8 for the last 20K miles and all is good. My engine has 330 ft lbs of torque which is more than a SRT. ""knock on wood". I talked to a shop that builds performance Nag-1/722.6 trans and was told the only difference was the clutch packs. The SRT trans is pretty much the same torque rating as most of the n/a V8's. The 55K had an even higher torque rating and the and the ones that were bolted to the twin turbo V12's had the highest rating. I am not sure how accurate the ratings are becasue the new 7 speed is rated hgher than the n/a V8 trans and has proven to be easier to break.

I would have thought I would have at least seen an "over toque" fault, but his has never happened. I haven't worried too much as replacement used trans are easy to find at resonable prices. I was also told that I could put my gearing into a V8 trans/case which would result in my excellent gearing with higher torque capability. One reason, my trans might be holding up is due to the fact that MB also put the V6 and V6 version trans in the big S class. Our cars weigh a lot less which helps the trans. Btw, my tans also has 93,000 miles on it. The only problem I ever had was the speed sensor which is part of the conductor plate going bad. I replaced this a couple of weeks ago and installed the blue tops at that time.