My friend has one with the automatic transmission and he says it is shifting hard. It appears to be a sealed system. Can those be drained by any shop or is that a dealer only thing?

I think "sealed system" is just marketing speak for "we cheaped out on providing a dipstick tube"

It probably has the same 4T45 that's in my Cobalt. I think it can be drained, but it's a PITA because there's no dipstick tube to pour fluid in.

This diagram might help:

IIRC the manuals used to say to warm the trans fluid for a few minutes, to something like 105-110° then remove the check plug. It should just begin to run out when filled correctly.

I don't know about an '05 but a number of late 90's-early '00s 4T40Es used to have issues with the pressure control solenoid causing poor shift quality.