Gear Question

The difference is one is made by Ford Racing Performnace Parts. The other is manufactured by Ford theirselves. Personally, there isnt much of a difference. People will tell you that the FRPP gears are more designed for racing yet I know of a guy who races a 500+rwtq t-bird and he uses OEM Ford 4.10 gears in his rear with no problems. I too will be putting OEM 4.30 Ford gears in my automatic car in the near future.