Mike if this is against the rules to post about this vehicle please delete. I have started doing all the maintenance on my parents vehicles and the Sienna has a bad pull to the left. What causes this? I have checked fronwheel bearing play but nothing. Stuck calipers? Thanks! 

Check alignment / bent suspension parts. 

 

Also try cross rotating the front tires to check for a lateral pull. Could be a manufacture defect

 

Brakes sticking could be a possibility, but you could tell if they are hot to touch the wheel.