you would have to check the code in the glove box and call the local parts store and have them tell you what rear end goes on the Yukon and then find out what rear end the 1990 rear end is and if they are the sam gear ratio then they ar enter change able .
The 2011 GMC Yukon has 65.2 in. of rear shoulder room.
The 2005 GMC Yukon has 65.1 in. of rear shoulder room.
The 2015 GMC Yukon has 60.3 in. of rear hip room.
The 2001 GMC Yukon has 38.6 in. of rear leg room.
The 2012 GMC Yukon has 60.6 in. of rear hip room.
The 2012 GMC Yukon has 39.0 in. of rear leg room.
The 2002 GMC Yukon has 39.4 in. of rear head room.
The 2008 GMC Yukon has 39.2 in. of rear head room.
The 2005 GMC Yukon has 38.6 in. of rear leg room.
The 2005 GMC Yukon has 61.3 in. of rear hip room.
The 2008 GMC Yukon has 60.6 in. of rear hip room.
The 2009 GMC Yukon has 39.2 in. of rear head room.