All Spicer® ring gear and pinion sets are designed and tested to meet original equipment specifications. They're built to the latest designs, which include premium heat treat processes and the most optimum tooth profiles, plus high-grade steel to achieve maximum durability. Remember: Non-genuine replacement parts are usually not manufactured to the same standards, which can cost you more in the long run. Reduce your downtime and cost with genuine Spicer® OE products.