Gears & Axles - Best gear oil for break-in, couple other ??s

I am getting 3.73s installed into my original 2.73 rear. I went with the thick series for the 2 series carrier and was wondering what is the best gear oil to use for break-in period? Also should I change the fluid after so many miles?

What is some of the methods as far as driving goes for breaking in the gears?
I was told to drive 10 miles, let it cool. drive another 10 miles. Let cool and continue doing this for the first 50 miles. Then take longer trips like 20 - 30 miles at speeds under 55. Any sugestions would be appreciated.

Thanks

thats correct in not driving on them for extended periods until you get 500 miles on them.

just use any oil then change it at 500 miles.i went with lucas.

Kendal or Wolfs Head 80W-90