About 2 years ago I found some really neat parts from Schumacher (sp). I think they are called 'blades'. I regularly run a 9 turn double in my car and have had no mishaps as yet. also they cut the wear down to nothing and there is no slop in the composite shafts (bones) and the diff half.

http://www.racing-cars.com/usa/produ...ecnumber=57725

Try this web page. I guess now they come on the shafts already. Who knew?