To replace the gears.....Unitrax can help you out, I think their kit includes everything inside the carrier. i.e. clutches, shaft,gears but i'm not 100% sure. What I did was order the complete Mopar performance carrier from my local dodge dealer and took all the guts out of it and put in mine. The mp carrier is for 1/2 inch ring gear bolts. Stock is 3/8 bolts so you would have to get a new gear and re...set up the gear in the housing to use the carrier, but the internals are the same. My dealer gives me a great price and there is no shipping charge and I now have a spare big bolt carrier if ever needed. Seems like Unitrax was in the $225 range for internals and dealer cost is about $190 on the complete carrier......get the dealer to sell it at 10-20% over cost and you will come out better. If yu can't get a dealer to work with you let me know. Also, Serpent what was replaced the first time ? A single gear or all four or??