I broke my inner splines on driver side within the differential on my Superformance Ford 8.8 rear end. All it took to eliminate the part was drag radials and one 3000 rpm start. All of my other starts before and after the incident have been near idle rpm. The half shaft chunks that were left over looked to be heat treated cast metal with mini hallow spots in the structure here and there in the middle.
I bought a new set of half shafts from
DRIVESHAFTS SHOP: Stock, Performance Drive Shafts, Aluminum Drive Shaft, Racing Axles that are said to be stronger. Of course the little broken bits and chunks filled the differential and rear end too. I put in a Detroit Trutrac rear end to replace the other.