Just a note too: Since is has been quite a few miles on the current differential fluid...do it right and completely remove the diff. cover. and drain and clean it this way. It is SUPER easy.<P>I use brake cleaner or an engine degreaser when I clean mine out, I do it yearly as I am VERY hard on my differentials.<P>Wipe it out with a towel or whatever, then refill with favorite fluid.<P>I use 80/140 in both FRONT and REAR differentials and NEVER had a problem with noise, outside of slight driveline vibe from pinion angles.<P>Good luck! <P>PS It took me about 45minutes to do my front differential the very first time I ever did it myself...that included going to the bathroom, drinking an adult beverage, feeding the dog...you get the picture...it is an EASY do it yourself job, at least on the rear diff...the front IFS diff can be kinda hard to get to depending on your vehicle/make/model.<P><BR>EDIT: The limited slip units that come stock on 99% of ALL vehicles do wear out eventually. The only kind that will last nearly as long as the vehicle is a gear driven limited slip such as the Detroit True-Track.<p>[ 18 September 2001: Message edited by: CerOf ]