Bought this and a YKF10.5-A Rebuild Kit to rebuild a 2001 F-350 SRW 4X4 Powerstroke with a 6 1/2" lifter and 37" BFG after a bearing failed at 210,000 miles . Excellent quality, the 4.30 gear ratio keeps the truck within 2% of the original 3.73/285 track width. I highly recommend this seller and this line of products.