I have a 89 chevy 1/2 ton 4×4 with a few mods done to it. not really the serious offroad truck but it does see its use. i have rebuilt the rear end (10 bolt) three times due to poor work from a shop 1 time and twice from mechanical failure. I have killed it again with my stupidity of using it as a tractor. I want a strong bolt in with 4.56 gears and still be able to run my six lug wheels since they are new and fairly expensive. I am running 35 14.50 tires on it and do know that it is not the best for the truck. any help for some good companies to check into will be greatly appreciated.