How do I know the vehicle is AWD
Perhaps this will answer your question, http://www.edmunds.com/buick/rainier/2006/features-specs/
There is an AWD version, and I'm afraid you'll have to check the VIN or look more carefully at the vehicle you're considering. http://www.edmunds.com/buick/rainier/2006/st-100565850/features-specs/
At 14 mpg city and 20 highway, I would think that there would be better choices out there. Just my two cents.
Looking for a Used Rainier in your area?
CarGurus has 385 nationwide Rainier listings starting at $1,850.
Search Buick Rainier Questions
Buick Rainier Experts