I would like to keep my 4L65 in my truck but, it is still having trouble taking the crap I am pushing through it. I do not want to purchase a complete trans. Maybe some pump upgrades or another reaction shell?
I see that cmotorsports has a tranny that puts up with 1000hp and 4500 pounds.

 

Call Carl Rossler at Rossler Transmissions. He builds some of the strongest transmissions out there. I've used his 4L60E and his level 4 Turbo 400 super tought trannys with no complaints at all.

Carl will stand behind his products and without a doubt his transmissions will put up with some big power! I do believe he also sells parts seperate for buildups. Parts like his Rosslock Transbreak and what not. Give him a call.