The 5.4L engine in the Navigator will take about 6 quarts. After adding 5, just add the last quart a little at a time and check the dipstick.
According to the 1999 Lincoln Navigator Owner Guide : For the 5.4 liter V8 engine ( 2 valve and 4 valve ) With engine oil filter change : ( 6.0 U.S. quarts of 5W-30 engine oil )
6 quarts
According to the 2001 Lincoln Navigator Owner Guide : With engine oil filter change : ( 6.0 quarts of engine oil )
According to the 2008 Lincoln Navigator Owner Guide : With engine oil filter change : ( 7.0 quarts of engine oil )
5 Qts. of oil
With engine oil filter change ( 7.0 quarts ) according to the 2011 Lincoln Navigator Owner Guide
According to the 2004 Lincoln Navigator Owner Guide : With engine oil filter change ( 7.0 quarts )
According to the 1999 Lincoln Navigator Owner Guide : With engine oil filter change : The 5.4 liter V8 engine ( 2 valve and 4 valve versions ) takes : ( 6.0 U.S. quarts of 5W-30 )
According to the 1998 Lincoln Navigator Owner Guide : With engine oil filter change : ( 6.0 U.S. quarts ) of 5W-30 engine oil
According to the 1998 Lincoln Navigator Owner Guide : With engine oil filter change : ( 6.0 U.S. quarts )
According to the 2001 Lincoln Navigator Owner Guide : With engine oil filter change : ( 6.0 U.S. quarts of 5W-30 engine oil )
With engine oil filter change ( 6 quarts ) according to the Owner Guide