THE STRONGEST SUPER HEAVY DUTY UPGRADED COMPLETE PLANETARY ASSEMBLY, WILL FIT ANY C6/E40D/4R100. NO MODIFICATIONS NEEDED. SET INCLUDES:HARDENED STEEL 6 PINION FRONT & 24 LUG STEEL 6 PINION REAR PLANET(INSTEAD OF 3 PINION ALUMINUM),HARDENED HEAT TREATED  HEAVY DUTY SUNGEAR & DRIVE SHELL,BEARING STYLE HUB ASSEMBLY(INSTEAD OF WASHER TYPE)ALL HEAVY DUTY RING GEARS & COMPLETE BEARING ASSEMBLY. ***EVERYTHING YOU NEED TO INSTALL IT!