RE: Shenqqi Diff
Use diff gear set from Duratrac.....Firehammer...they are the same as what you have now.....only better gears....The cost is like$39.95 USD......
You can go FG rear diff....but you also have to use different inner & outer drive cups.....as well.....repairs for the internal Fg diff is very costly......
That is my suggestion on using the Duratrac diff gears...........Slawhammer