$1500 installed for a front and rear master kit. I ran the 3.73' with my 37's and it was a turd. I went to the 4.56's and love them. The again I don't run down the road at 80 mph's but at 70mph I'm looking like 2250 - 2300 rpms without a tow load. I'm a red light to redlight kind of guy...