I used Red Line V-Twin Transmission w/ Shockproof. Red Line's site says it's the same as the Heavy Shockproof gear oil. My Harley dealer doesn't stock the gear oil anymore.

http://www.redlineoil.com/product.aspx?pid=119&pcid=13

 

I love the stuff in my tranny, I'm also using the Redline Primary fluid in my Primary but still run Amsoil in the Motor.