97 and up the 8.25 had 29 spline shafts 96 and earlier had 27 spline shafts if yours is a 94 and has the factory rear its a 27 spline and i believe that the dana 35 is 27 spline i could be wrong about that though

 

Yes, the 94 C/8.25 had 27 spline shafts and so did the D/35, but the Ring & Pinion are both stronger on the C/8.25. The C/8.25 also has 3 inch tubes whereas the D/35 has 2.5 inch tubes those differences make the 27 spline C/8.25 much stronger than the D/35 axle, and the C/8.25 is easily upgradable to the 29 spline shafts.