I wasnt expecting this at all when I tore my tranny down . The sun shell ballooned up and the top portion of the wall turned into lots of quite large chunks of metal lodged everywhere at the same time taking out the low reverse input drum ....only the portion that sits over the sunshell . The Sun shell was and HD Art Carr ( the real one ) piece . The portion thats reinforced on the bottom where roller bearing ( used to be a thrust washer ) sits was the only part of this thing that was intact and not all ballooned up . It was so lodged in the case it took about an hour to get it out . After close inpection of EVERYTHING else , the was no other damage at all . All the clutches , 2-4 band yadda yadda all looked like brand new . So Im clueless as to what would cause this . It happened on the 1-2 shift , just after it hit 2nd at 6900 rpm's .

 

Too much power!!! Typically the sun gear strips. I've never heard of the sun shell ballooning and breaking up like this. The reverse input drum is a pretty stout unit and shouldn't have sustained any damage. Call Art Carr and see if they will warranty this for you. It sounds like it may have been weak to start out with. Does this one have the cut outs in it to lighten it up? If so, maybe this contributed to it. How did you hit 6900 in a 4l60e? You're close to bending valves.

 

I'm gonna spare the headache of calling Art carr , I cant see how they would cover something like this . I just wanted to know what the hell would cause this . I seriously doubt Im making too much power for this transmission , its pretty extensively built . Probabaly was just one of those things I guess .

I'm nowhere close to bending valves

 

When I was running nitrous on my 93 I did this twice, we bought the heavy duty one from Bowtie overdrives and it never happened again.