According to the 2006 Ford Mustang Owner Guide :
With engine oil filter change :
The 4.0 liter SOHC , V6 engine takes :
( 5.0 U.S. quarts / 4.7 liters of 5W-30 )
5 quarts
Put oil in it and Use the dipstick to see how much is in there.. when it gets full that's how much goes in there! Einstein.
( 6 quarts ) with engine oil filter change on your 4.6 L - 2006 Ford Mustang
The 2006 Ford Mustang V8 engine take 6.0qts of oil
According to the 2006 Ford Mustang owners manual ( 5W-20 engine oil ) is used in the 4.6 liter 3V engine
With engine oil filter change ( 6 quarts ) for the 4.6 liter V8 engine according to the 2010 Ford Mustang Owner Guide
That is the oil filter
5 quarts total, 4 in the tank and one in the filter
In the Mustang of that year having a 6.75 in. rear end in it you would need 2.5 pints of gear oil. This is 90 wt. oil. If you have a 7.50 in. rear end, you would need 3.5 pints of the 90wt oil.
4.5 quarts
The recommended oil is SAE 5W-20
Oil capacitie on the V8 is 6.0qts