From the 2006 Scion xB owners manual (pg 229):
Recommended oil viscosity: 5W-30
Oil Capacity:
w filter 3.7 Liters / 3.9 quarts / 3.3imp quarts
w/o filter 3.4 Liters / 3.6quarts / 3.0 imp. quarts
4.2
3Q but pick up 4Q
4 quarts
4 quarts
4 quarts
4 quarts
4 quarts
3.9 but 4 will work just fine
If you mean how many quarts of oil it's 4 if you're also changing the filter. Less if you're not changing the filter.
5.5 quarts
How many quarts of oil does a 2005 infiniti ax56 take
6 Quarts of oil in the 2.5T