What have they really done to the 2011 Allisons?

[cowboywildbill]

Does any one know how beefed up the 2011 Allisons really are?
What are the real differences in the drive train?
Did they put different style clutch packs like aftermarket style one's in them and did they go with a bigger better torque converter?
And is the trans brake same as previous years or is it actually a retarder like an exhaust brake?
Also are they still running the same transfer case and if so did they modify the clip on the pump shaft that causes the dreaded wear hole in the cases? Just curious.

[THEFERMANATOR]

I don't know all of the upgrades, but I do know the 2011 ALLISON is a whole new animal from the older model. They now have a solonoid in them to adjust line pressure whereas older models used a fixed valve to regulate it. There has also been some internal changes, but I haven't seen the differences side by side yet.