I have a 2006 Malibu LS with blown motor and a 2007 impala. My question is can I swap the Malibu motor with the impala motor without removing the transmission?

 

Depends, you might. I will assume you have an automatic transmission with an Impala, I've never seen it done, but with the torque converter to deal with, it may or may not
be possible.

Mayhaps someone else here can give you better advice on this matter. With a stick-shift you would have to align the pilot bearing or bushing with the transmission input shaft but with an automatic it _might_ be possible.. I think that it may not be only because of the torque converter issue..And of course, you will need to move the transmission cooling lines to the radiator in order to do so.