I can think of a few things here, th extreme CV angles certainly aren't helping, they'll put some nasty loads on the diff, but the 20'* are VERY heavy, and probably don't light up for crap. If you try to spin your tires i bet only one is going with those suckers, causing problems...

well time for a new one with a 24k warrenty

is there some kind of defects cause im on my second tranny for my bonnie and i know im not the only bonnie to have tranny problems what is with these trannys did gm say one day "hey lets put the crappiest tranny in such a great car to annoy those poor owners"

new tranny pics

1250$ US 18month/18000mile

install starts in a few hours after i take a nap

also that does include a reman torque converter

Well good for you. I wish I could get a new tranny, mines throwing codes so the dealer says.

I dont think ride height will have any affect on the tranny at all.....I work at a body shop...and have seen axles ripped in half....completely tore out of the tranny....the tranny always is fine....the tranny is one tough beast....the axles are the most fragile part of the driveline...next to the wheel bearings....