I am going to be installing an ud pulley myself and i am wondering if I should chang the oil seal.I heard people talking about it, are they talking about the aluminum sleeve on the pulley, or is it something else. Its an unothadox and it does not say anything about it in the directions.

 

Change the oil seal. Get one from your Nissan dealer for about $5-6. Instructions on changing the UDP for a 2002-2003 are available on my webite (click homepage on the left).