Just took out my Detroit Locker and put in the TrueTrac I had. I filled with 90wt gear oil but whats your opinion - is there a better oil? Someone suggested regular motor oil.
I think the heavier weight (heavier than motor oil) is more for the gears and the bearings than the LTD. I use an 85/140wt as my cheap gears are a little noisy.
I hope you like your Truetrac as much as I like mine!