Strange Engineering only uses the highest quality gears available from U.S. Gear, Motive Gear, Richmond and Dana/Spicer for S60 and Dana 60 applications. The Dana/Spicer pro street gears provide excellent life for circle track, street and some drag race applications. The 9310 pro gears are designed drag racing only and absorb high impact shock loads that occur in straight line racing applications. When investing in a new ring and pinion, it is important to use new bearings, seals, ring gear bolts and other essential installation components. Strange offers a wide selection of installation kits to compliment the full line of gears.