ORIGINAL: burnchassis3
I assure you he is wrong.
Heavy in rear light in front.
Light oil allows the diff to slip almost as if there was no grease in it,Heavy will lock it up..almost like a locker would,but allowing a little give for hard landings.
Heavy in front will give you a POSI effect in the front..making your truck PUSH more in the turns.
Light in the rear will allow 1 of the tires to spin more then the other ...usually the inside wheel "One wheel peel" therfore your losing traction.
CS
I did a search and another member runs heavier oil up front. The LHS owner said something about the front being able to pull you through turns and the ass end not sliding out as much. I will do a search and posts a link to the post from the member here that runs heavier oil up front.