I guess i will point out that he has a 4L60e trans and says it is stuck in 2nd gear.. the default gear on a 4L60e is 3rd gear as pointed out in the TSB that was posted too.
Default on the 4L80e trans is 2nd gear.
Perhaps the vehicle owner does not know what gear the trans is stuck in? Lets hope he finds the problem easily
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.