The transmission is NOT the same as others. its a hybrid version of the 46RE. with a different bellhousing to fit the starter on the right side.
the 46re is a good tranny. it comes in all 5.9 dodge rams (1500/2500)
Reliability on mine has been so so, i've had to replace a few things in the last 6 months, Crankshaft position sensor TWICE (first was not a mopar unit) at $120 for a sensor it sucked, but installation was horrificly difficult.
Fuel pump went, had to drop the skidplate and tow package to drop the tank. took almost a day.
electrical bugs constantly shadow me, my sunroof is on the frits (bad track cable) heated seats have failed, internal issue in the seat.
Besides the 5.9/46re combo, the rest of the stock drivetrain is damn near junk, from the D44a rear that is prone to fail and expensive to fix, the 249 Transfercase that has a smaller fanclub then the disease AIDS.
The stock front axle is a Low-pinion dana 30, with CV axle shafts, the front Driveshaft is also a CV unit. (terribly weak but cheap to upgrade)
I have to say tho, Besides being a pain in the azz, i love it. It's fun to drive, extremely Capable offroad, and comfertable. And easy to upgrade, they can be more expensive then an XJ for some repairs/upgrades, but In my opinion, worth it!
Disclaimer: mine has 180k!
edit: a good forum for 5.9s www.thespeedfreaks.net