Need some info

There is no difference in the engine or transmission. The base model has cloth interior and as you go up in models, you get leather and certain options become standard. You would need to find a 2011 sales brochure to determine exactly what was added to each model. As an example, I have a 2016 brochure....there was the base Enclave, then the Leather group added...heated steering wheel, leather seating, 8 way power heated front seats, driver memory, side blind zone alert, rear cross traffic alert. premium group added,....sound and navigation, 19"wheels, power folding outside mirrors, articulating headlamps, tilt and telesoping steering wheel , forward collision alert, lane departure warning, bose sound system, cooled & heated front seats. Remember that is for a 2016 and some of those options were not available in 2011, also some of them could be ordered even on the base car.