Just picked up a clean .08 Chrysler aspen (durango) its got the standard radio is a swap to the oem radio/nav unit a simple plug and play swap??? they are cheap on fleabay....

Does it have steering wheel controls?

yep....

Is it a double Din size or oddball size radio?

i built at least 100 of these as salvages. more than likely you dont have the correct nav antenna or wiring. you also might need to have a dealer flash the computer . the nav for these cars is really bad by new car standards, fyi

Probably need the antenna as mentioned
Buddy has a 08 pickup with Nav, and the maps needed updating. Bought the update thru Chrysler (USB stick) and soon as it was plugged in, a Y/N question came up, then Nav unit took over and installed it